Home General Knowledge GENERAL AWARENESS : QUIZ - 8
GENERAL AWARENESS : QUIZ - 8
Wednesday, 30 April 2014 06:44




GENERAL AWARENESS : QUIZ - 8


NO.

QUESTION

ANSWER

01

The theory of relativity was propounded by

Albert Einstein

02

The principal metal used in manufacturing steel is

Iron

03

An alimeter is used for measuring

Altitude

04

Oology is the study of

Birds eggs

05

Radioactivity was discovered by

Henry Bacquerel

06

The metal used in storage batteries is

Lead

07

The instrument used to measure the relative humidity of air is

Hygrometer

08

Barometer was invented by

Torricelli

09

The unit of power is

Watt

10

Radium was discovered by

Marie and Pierrie Curie

11

The existence of isotopes was discovered by

Frederick Soddy

12

Dynamo was invented by

Michael Faraday

13

The nuclear reactor was invented by

Enrico Ferni

14

The law of gravitation was propounded by

Sir Isaac Newton

15

Crescograph was invented by

J.C.Bose

16

Crescograph is used to measure the

Rate of growth of a plant

17

Galileo's first scientific discovery was

Pendulum

18

Microscope was invented by

Aaton Van Leewen Hock

19

The scientist who is known as father of modern biology is

Aristotle

20

The first person to see a cell under microscope was

Robert Hooke

21

The smallest flowering plant is

Worffia

22

The four blood groups were discovered by

Karl Landsteiner

23

Sodium was discovered by

Sir Humphry Davy

24

The atomic number of oxygen is

Eight

25

The basic building blocks of proteins are

Amino acids

26

The botanical name of the cotton plant is

Gossipium Hirsutum

27

An Electroscope is used to

Detect charges on a body

28

The unit of loudness is

Phon

29

An ammeter is used to measure

Electric current

30

Plant that eat insects are called

Insectivorous plants

31

Fruits that are formed without fertilization are called

Parthenocarpic

32

Plants that flower only once in their lifetime are called

Mono carpic

33

The botanical name for rice is

Oryza Sativa

34

Penicillin is obtained from

Mould

35

The largest tree in the world is

Seguoia Gigantica

36

Herpetology is the study of

Reptiles

37

Entomology is the study of

Insects

38

Ornithology is the study of

Birds

39

Ichtyology is the study of

Fishes

40

Osteology is the study of

Bones

41

The botanical name for brinjal is

Solanum melongenal

42

The botanical name for onion is

Allium Cepa

43

The study of sound is called

Acoustics

44

The study of heavenly bodies is called

Astronomy

45

The study of tissues is called

Histology

46

Electric Lamp was invented by

Thomas alva Edison

47

The fear of crowd is called

Ochlophobia

48

The fear of books is called

Bibliophobia

49

The fear of going to bed is called

Clinophobia

50

The symbol of gold is

Au

51

The symbol of sodium is

Na

52

The symbol of Sr stands for

Strontium

53

The symbol Rb stands for

Rubidium

54

The symbol Md stands for

Mendelevium

55

Calcium sulphate is commonly called

Plaster of Paris

56

Sodium carbonate is commonly called

Washing Soda

57

Sodium chloride is commonly known as

Common Salt

58

The chemical name of Chloroform is

Trichloromethane

59

The chemical name of baking powder is

Sodium bicarbonate

60

The chemical name of bleaching powder is

Calcium hypochlorite

61

The formula HCL stands for

Hydrochloric Acid

62

The formula H2SO4 stands for

Sulphuric Acid

63

The formula CHCI3 stands for

Trichloromethane

64

The formula H2O2 stands for

Hydrogen peroxide

65

A fungus which can only survive on other living organisms is called

Obligate Parasite

66

A plant which lives in the dark is called

Scotophyte

67

A plant adapted to live in dry places is called a

Xerophyte

68

A plant adapted for growth in water is called a

Hydrophyte

69

Bifocal lens was invented by

Benjamin Franklin

70

Cement was invented by

Joseph Aspdin

71

Laser was invented by

Dr.Charles H.Townes

72

Electromagnet was invented by

William Sturgeon

73

Rayon was invented by

Sir Joseph Swann

74

Thermostat is an instrument used for regulating

Constant temperature

75

The science of organic forms and structures is known as

Morphology

76

Phycology is the study of

Algae

77

Tata Institute of Fundamental Research was established in

1945

78

CSIR stands for

Council of Scientific and Industrial Research

79

ISRO stands for

Indian Space Research Organisation

80

The first human being to land on moon was

Neil Armstrong

81

The first Indian in space was

Rakesh Sharma

82

ISAC stands for

ISRO Satellite Centre

83

VSSC stands for

Vikram Sarabhai space Centre

84

The headquarters of ISRO is located at

Bangalore

85

VSSC is located at

Thiruvananthapuram

86

ISAC is located at

Bangalore

87

National Science Centre is located at

New Delhi

88

Central Tobacco Research Institute is located at

Rajahmundry

89

Indian Institute of Horticultural Research is located at

Bangalore

90

The Atomic Energy Commission was set up in

August 1948

91

The first Indian Satellite was

Aryabhatta

92

The first Indian Satellite was launched in the year

1975

93

ASLV stands for

Augmented Satellite Launch Vehicle

94

INSAT stands for

Indian National Satellite

95

The fear of women is known as

Gynophobia

96

The fear of men is known as

Androphobia

97

The scientist who developed the Quantum theory was

Max Plonck

98

The steam engine was invented by

James Watt

99

The botanical name of tea is

Camellia Sinensis

100

Logarithms were devised by

John Napier

101

The acid used in a car battery is

Sulphuric acid

102

The system for writing by blind people was invented by

Louis Braille

103

The parachute was used for the first time by

J.P.Blanchard

104

The German physicit who first demonstrated the existence of Radio waves was

Henrich Hertz

105

The instrument that records the intensity of earthquakes is

Seismograph

106

The laws of floating bodies was discovered by

Archimedes

107

The density of milk is measured by a

Lactometer

108

Fountain pen was invented by

L.E.Waterman

109

The instrument used to measure the pressure of gases is the

Monometer

110

Bhaskara I was a famous

Astronomer

111

The first atomic power station established in India was the

Tarapore Atomic Power Station

112

The role of heredity was demonstrated by

Mendel

113

The instrument used to measure the concentration of salt water is the

Salinometer

114

Spectroscopy is the study of

Anders John Angstrom

115

Dactylography is the study of

Finger Prints

116

A tangent galvanometer is used to study the

Strength of direct current

117

The fruit of Oak is called

Acron

118

ZETA stands for

Zero Energy Thermonuclear Assembly

119

The formula C6H5OH stands for

Phenol

120

Michael Faraday worked as an assistant under another scientist whose name was

Sir Humphry Davy

121

Vulcanised rubber was invented by

Charles Goodyear

122

The symbol Zn stands for

Zinc

123

The symbol He stands for

Helium

124

Celluloid was invented by

A.Parker

125

Glider was invented by

Sir George Caley

126

Safety matches was invented by

J.E.Lundstrom

127

Radio valve was invented by

Sir J.A.Fleming

128

Space Applications Centre is located at

Ahmedabad

129

Atomic Energy Commission is located at

Mumbai

130

Dynamics is the study of

Movements of bodies

131

Statics is the study of

Forces acting on bodies at rest

132

Mechanics is the study of

Forces acting on bodies

133

Zoology is the study of

Animal life

134

Botany is the study of

Plant life

135

Psychology is the study of

Human mind

136

The first American to orbit earth was

John H.Glen

137

The electro-cardiograph was invented by

William Einthoven

138

The molecular formula of cane sugar is

C12H22O11

139

A compound which contains only hydrogen and Carbon is called a

Hydrocarbon

140

The liquid used to preserve specimens of plans and animals is

Formalin

141

The law of segregaton was propounded by

Mendel

142

Auriscope is used to detect

Ear disorders

143

The three states of matter are

Solid,liquid and gas

144

The scientific name for blood platelets is

Thrombocytes

145

The response of a plant to heat is called

Thermotropism

146

The response of a plant to touch is called

Trigmotropism

147

The symbol Zr stands for

Zirconium

148

Nickel was discovered by

Cronstledt

149

Manganese was discovered by

Gahn

150

The common name for pottasium carbonate is

Potash

151

Bismuth was discovered by

Valentine

152

The biggest plant seed is

Cocodemer

153

Toxicology is the study of

Poisons

154

Virology is the study of

Viruses

155

Paleontology is the study of

Fossils

156

Calorimeter is used to measure

Quantity of heat

157

Chronometer was invented by

John Harrison

158

Stethoscope was invented by

William Stockes

159

Spinning frame was invented by

Sir Richard Arkwright

160

Al stands for

Aluminium

161

Gd stands for

Gadolinium

162

Ir stands for

Iridium

163

Bi stands for

Bismuth

164

The Chemical formula of sodium bicarbonate is

NaHCO3

165

The chemical formula of common salt is

Nacl

166

The chemical formula of washing soda is

Na2CO3,IOH2O

167

The chemical formula of lime soda is

CaCO3

168

The chemical formula of chloroform is

CHcl3

169

The study of grasses is known as

Agrostology

170

The study of antiquities is known as

Archaeology

171

The study of the duration of life is known as

Chronobiology

172

The study of bacteria is known as

Bacteriology

173

Nylon was invented by

Dr.Wallace H.Carothers

174

Electric razor was invented by

Jacob Schick

175

The symbol of silver is

Ag

176

The symbol of silicon is

Si

177

The symbol of titanium is

Ti

178

Calcium oxide is commonly known as

Quick lime

179

A deviation of light passing from one medium to another is known as

Refraction

180

An apparatus for generation of atomic energy is called a

Reactor

181

A machine used for converting mechanical energy into electrical energy is called a

Generator

182

The first Indian woman in space was

Kalpana Chawla

183

The revolver was invented by

Samuel Colt

184

The refrigerator was invented by

J.Perkins

185

Which is the only common metal that is liquid at room temperature?

Mercury

186

When a fire is caused by an electric short circuit, why must you not throw water?

If you throw water on a fire caused due to short circuit, you may be electrocuted because water is a good conductor of electricity.

187

Why do we see lightning much before we hear thunder?

This is because light travels much faster than sound. Light travels @ 2.99 x 108 mt / sec (2,99,000 km/sec) whereas sound travels @ 333 mt/sec.

188

Which planet is the closest to the Sun?

Mercury

189

Which is the hottest planet?

Venus

190

How much time does the earth take to complete a revolution around the sun?

365 % days.

191

Why are whales hunted?

For the blubber or the oil in them.

192

Where do platypuses live?

In burrows near water.

193

How many days does the moon take to go round the earth?

27 1/3 days.

194

Among the insects that are extant, (that are living still), which is the most ancient?

Cockroach.

195

What is meant by fulcrum?

Fulcrum is the point about which a bar or lever will rotate, when a force is applied at any distance from that point or axis.

196

What kind of leaves do silkworms thrive on?

Mulberry leaves.

197

Why is it dangerous to look at die sun during an eclipse?

During solar eclipse, the ultraviolet rays are in such high proportion in sunrays, that they can cause irrepairable damage to the eye.

198

How does a Pitcher Plant eat flies?

A Pitcher Plant is hollow and tubular. The surfaces are slippery and they have hairs, which point downwards. When an insect lands on a pitcher plant, it is impossible for it to escape because of the slippery surface and the downward-pointed hairs. It is then easily digested.

199

What is the Indian name for the planet Mercury?

Budha.

200

Where in India do the migratory cranes of Siberia settle down?

The Rann of Kutch.

201

How many arms does a starfish have?

Usually five.

202

What is a solar eclipse?

The moon comes in between the sun and the earth, and thereby prevents sunlight from reaching the earth.

203

Who first saw mountains and craters on the moon using a telescope?

Galileo Galilei

204

Which is the largest animal on land?

African Elephant.

205

Why does a rhinoceros spend so much time in mud?

To keep cool and protect itself from insect bites.

206

Which country first used fingerprints to identify people?

Assyria and China.

207

In which country was silk first made?

China.

208

What is cholesterol?

Cholesterol is a fat found in the human body and the body of other large animals. In its pure form it looks like white sugar. It is made up of tiny crystals, which can be seen under a microscope. It is said that too much cholesterol in the blood is responsible for the hardening of arteries and for various other heart ailments.

209

How did the watch get its name?

From the fact that you have to watch it to know the time.

210

What is vulcanisation of rubber?

The process of hardening rubber by adding sulphur and heating the mixture is vulcanisation. Vulcanisation was discovered by Charles Goodyear. Raw rubber is sticky. It hardens when the temperature is low and softens when it is high. Charles Goodyear discovered that by combining raw rubber with sulphur and by heating it, the rubber becomes stronger and elastic and also resistant to solvents. Today almost all rubber, whether natural or synthetic is vulcanized.

211

When faced with danger what does a Pangolin do?

It rolls into a ball.

212

Where is the entrance to a baya's nest?

At the bottom of the nest.

213

What is glass made from?

Limestone, Silica and Soda ash.

214

What is the microscopic study of plant and animal tissue called?

Histology.

215

How does a mariner's compass help the mariner?

The needle of the compass always points towards the magnetic north pole. This indicates the direction in which the ship is moving.

216

Which is the second largest planet in our Solar System?

Saturn.

217

How many weeks after birth does the young one of a cat opens its eyes?

Three weeks.

218

The arms of the Octopus have sucker cups. What is the use of these cups?

To hold onto a surface.

219

What food does a bear love most?

Honey.

220

How did the Romans rub off what was written on a wooden slate coated with wax?

By heating the slate, the wax was melted. The slate became ready to reuse.

221

What are seashells?

Outer casings of soft-bodied animals, called molluscs.

222

How is a pearl formed within the body of an oyster?

A pearl is formed when a grain of sand or other foreign matter gets between the hard outer shell and the inner coat called the mantle, of a mollusc. The mollusc surrounds the irritation with nacre, a secretion from the mantle. Many thin layers of nacre give the pearl its lustre.

223

How much time does Pluto take to complete a revolution around the sun?

248 years.

224

What is a Catamaran?

A boat with twin parallel hulls. [From the Tamil words katta and maram, meaning tied up (katta) tree (maram).

225

How many ears does a spider have?

None.

226

How much time does light take to reach the earth from the sun?

8 minutes.

227

What is acceleration?

The time rate at which the velocity of a point is changing is acceleration. Velocity is just the speed (miles per hour or kilometres per second). The term acceleration is used when the speed keeps increasing. The term deceleration is used when the speed becomes less and less.

228

How does a spider eat its food?

The spider inserts his fangs into the victim's body and uses them as straws to suck out the liquid.

229

Who invented the telescope?

Hans Lippershey.

230

Why do people living in the deserts prefer white colour for their robes?

White coloured robes do not absorb light, whereas dark-coloured clothes absorb the light and conduct heat to the body.

231

What is common to dolphins and humans?

They are both mammals.

232

In which country was the day first divided into 12 parts?

Babylon (modern Iraq).

233

How does a rocket move forward?

It moves forward due to propulsion. You must have seen that a boatman pushes the water backwards with his oar. This creates a force in the forward direction. This is propulsion. Newton's third law of motion states action and reaction are equal and opposite. In a rocket when hot gases come out of the rear with great force as a result of combustion, a force is created in the opposite direction. This takes the rocket forward.

234

What are the things necessary to start a fire?

Heat, fuel and oxygen.

235

How many legs does a butterfly have?

Six.

236

Who invented the aeroplane heavier than an air machine that could fly?

Orville and Wilbur Wright.

237

Who invented the modern lift?

Elisha Otis.

238

Why can't cranes perch on trees branches?

They cannot curl their toes. As a result they cannot have a firm grip on a branch.

239

Ancient Sumenans used to write on clay. How could this writing be preserved?

By baking the tablets. This would remove the moisture from the tablets and harden them.

240

How big are the tusks of an Indian female elephant?

Indian female elephants do not have tusks.

241

Bats cannot see. Then how do they move about?

They emit sounds of low intensity, which are reflected from the objects around them. This helps the bats to move about.

242

How does a frog catch an insect?

It throws out its tongue, which is sticky and catches the insects.

243

What is a Portuguese Man of War?

A name commonly applied to jelly fish, found in tropical seas.

244

Why are oceans important to man?

They enable man to travel to distant corners of the world. They also provide food, oil and minerals.

245

What is the transparent portion in front of the eyeball called?

Cornea.

246

What is the meaning of the pecking order?

Pecking order is an example of hierarchy among animals, particularly hens. In a coup containing hens and cocks, the seniormost cock can peck at all the other hens and cocks in the coup. A hen can peck at others weaker than it, but must permit pecking by senior members in the hierarchy.

247

Who made trains run by steam engine popular?

George Stephenson

248

How are volcanoes caused?

Deep under the crust of the earth is molten rock or lava, also called magma. It is under great pressure because of the intense heat around it and the weight of the earth's crust. When this hot boiling mass finds an outlet in the underside of the earth's crust, it comes through the surface as lava.

249

What is a male ant called?

Drone.

250

How can a frog make such a loud sound?

As the frog forces air from the lungs, vocal chords in the voice box (larynx) vibrate to make calls, distinctive of its species. The bulls of some species have air sacs, which help, increase the volume of the sound.

251

Who was the first man on the moon?

Neil Armstrong.

252

What is peristalsis?

Peristalsis is a type of movement occurring in the hollow organs of animals, which causes their contents to be pushed ahead.

253

What are the main differences between an Indian elephant and an African elephant?

The African elephant is much larger in size. Its ears as well as tusks are larger than those of an Indian elephant.

254

What is it that silkworms weave around themselves?

Cocoon.

255

Why did Dr. Lister use carbolic acid to cover wounds?

To prevent infection.

256

What is the juice of the rubber plant called?

Latex

257

Why does the ostrich eat sand or gravel?

To digest its food.

258

Which discovery made soap-making a big industry?

It was discovered (in 1787) that caustic soda can be made from common salt. Since soap is made from caustic soda and fat, manufacturing soap became cheaper.

259

Who invented the Gramophone?

Thomas Alva Edison

260

Which is the largest living bird?

Ostrich.

261

Why didn't the British plant rubber in England?

Rubber grows only in tropical countries.

262

Why do tigers turn into man-eaters?

When tigers become old or are incapacitated because of injury, they prey on human beings. A tiger that has preyed on man and has tasted human flesh often continues to prey on man.

263

What was called Penny-farthing?

The cycle whose front wheel was much larger than the rear wheel. It was invented by James Starley. It was derisively named penny-farthing after the largest and smallest English copper coins of the period.

264

Why does not the moon have an atmosphere?

Even if it had some atmosphere, its mass is so low that gravity on the surface is not enough to retain the atmosphere.

265

Name the animal that has the largest eyes in the world?

The Atlantic Giant Squid, about 30 cm wide.

266

Who invented the four-stroke Motorcar engine?

Nikolaus Otto.

267

What are meteorites?

They are rocks or pieces of rocks that enter the atmosphere and are usually burnt out before landing on earth. Some large meteorites can crash against the surface of the earth and cause damage.

268

What did ancient Romans think lightning was?

Jupiter's weapon.

269

Are the soldier ants male or female?

They are all female.

270

What is the nest of a penguin made of?

Pebbles.

271

What are the characteristics of a parasitic plant?

They cannot produce their own food and obtain food from other sources.

272

What keeps the sun so hot?

A reaction similar to that of a hydrogen bomb takes place continuously in the sun. Two atoms of hydrogen fuse at high temperatures to form an atom of helium. Immense heat is released in this reaction.

273

What is meant by Binary System?

We carry out everyday calculations, using the decimal system, with the numbers 1 to 9 and zero. The binary system uses only two numbers 0 and 1. An electric current can be switched on and off using off for 0 and on for 1. Any number can be represented in the binary system.

274

Which was the first spaceship launched by man?

Sputnik-I, launched by the Russians

275

What kind of nests do owls build?

They don't build nests. They use hollows in trees for laying eggs.

276

Why is polished rice less healthy than unpolished
rice?

The husk of food grains (rice, wheat, etc) has Vitamins, much of which are lost when the grains are polished.

277

Which Psychologist devised the IQ test?

Alfred Binet.

278

Who discovered Radium?

Pierre and Marie Curie.

279

What is the approximate temperature deep inside the sun?

14 million degrees C.

280

What are Epiphytic plants?

Plants that grow on other plants for support. These plants however do not take nourishment from the host.

281

Sometimes the eagle spits out pellets from its mouth. What are they?

Bones and fur of the prey that are left after the food is digested.

282

What does a ruminant mean?

Ruminant is an animal that chews its cud and has a four-chambered stomach. When food is swallowed by a ruminant, it passes into the rumen or paunch, where it is stored, while the animal eats. Chewing and digestion are carried out at leisure. The food passes from the rumen to the reticulum, where it is formed into small masses and pushed up to the mouth to be chewed. When it is swallowed a second time it takes a different route. Gastric digestion takes place and the food passes into the intestine.

283

Who discovered the Planet Uranus?

Sir William Herschel.

284

Who invented Television?

John Logic Baird.

285

How do dolphins communicate with each other?

By producing screeching sounds.

286

Who was the first woman to travel in space?

Valentina Tereshkova.

287

What are clouds made of?

Tiny droplets of ice or water.

288

What is the disease that causes dogs to turn mad?

Rabies.

289

Who conducted the first controlled fission reaction (that led to the making of the atom bomb)?

Enrico Fermi.

290

Which was the first satellite launched by India?

Aryabhata, in 1975.

291

What is Dry Ice?

Solid Carbon Dioxide.

292

Who invented the Radio?

G. Marconi (Jagadis Chandra Bose has also been credited with this discovery but his claim has not been recognised).

293

What was the theory of the atom put forward by Rutherford?

Rutherford put forward the theory that every atom consists of a tiny nucleus with a positive charge, surrounded by electrons. The electrons are far apart from the nucleus and from one another.

294

Of which element is diamond made of?

Carbon.

295

The Pit Viper has poor eyesight. Yet it can locate its prey accurately. How?

It has heat sensory cells in the pits between the eye and the nostril, which detect warm-blooded animals.

296

Who first propounded the theory of Evolution of Man?

Charles Darwin.

297

From which elements is steel made?

Iron and Carbon.

298

Which instrument is used for measuring humidity?

Hygrometer.

299

If you speak loudly on the moon, approximately how far can your voice travel?

Sound waves need a medium in which they can travel. The atmosphere on the moon is negligible. Hence your voice cannot travel any distance.

300

What is the difference between Toads and Frogs?

Toads have a dry warty skin while frogs have a smooth moist skin.

301.

Who first discovered that water was produced by burning hydrogen?

Henry Cavendish.

302.

What are the parts of a comet?

Nucleus, coma and tail.

303

Why are the blades of the fan slightly curved?

If you wish to carry sand or any solid substance from one place to another, you can carry little if there are straight metal strips. A pail can carry much more. In the case of air, which is a fluid, a slightly curved blade is enough to help circulate air in the room.

304

What is absolute zero temperature?

Absolute zero is the temperature at which thermal energy (energy related to heat) vanishes. It corresponds to -273.15 degrees, on the Celsius scale.

305

Who is considered the father of plastic surgery in ancient India?

Sushruta. He is best known for the operations he performed called rhinoplasty (remodelling of the nose).

306

What are isotopes?

Isotopes are different forms of an element with the same number of protons, but a varying number of neutrons in the nucleus of an atom. All elements consist of atoms. Atoms have a nucleus, which consists of proton or protons and neutrons. They usually have as many electrons as protons, continuously whirling around the nucleus. Hydrogen has two naturally existing isotopes - one with only a proton and no neutron in its nucleus and another with a neutron and a proton. The first one is commonly known as hydrogen. The second one is rare and is called deuterium or heavy hydrogen. A third isotope, called tritium, is artificially produced. Tritium has one proton and two neutrons.

307

Who discovered the cause of malaria?

Ronald Ross.

308

Which planet has a moon named Titan?

Saturn.

309

Name the largest bone in the human body.

Femur (in the thigh).

310

What is the source of all energy on earth?

The sun.

311

What was the name of the instrument used by Jagadis Chandra Bose to measure sensitivity of plants?

Crescograph.

312

How long do banyan trees live?

Banyan trees seem to live for hundreds of years. Aerial roots develop from its branches and they take root in the soil. Over the years these roots turn into sturdy trunks, which too grow roots and the cycle continues. It is said that the entire army of Alexander had taken shelter under one such banyan tree.

313

Which part of the plant do you eat when you eat carrots?

Roots.

314

Who was the first man to travel in space?

Yuri Gagarin.

315

What is reinforced concrete?

Reinforced concrete is ordinary concrete which has steel rods fixed in it.

316

What is meant by latent heat?

Heat absorbed when a substance changes its state without changes in temperature, e.g. water boils at 100°C. When we heat it further the temperature is not raised but the heat is absorbed.

317

In ancient India shells of a sea-animal were used as money. What were they called?

Cowries.

318

How does spraying kerosene on marshes reduce mosquitoes?

A film of oil is produced which prevents the larvae of the mosquitoes from having access to the oxygen in the atmosphere.

319

How many bones are there in an adult human being?

206.

320

Who is considered to be the father of Geometry?

Euclid.

321

What is the study of sound called?

Acoustics.

322

Which was the first satellite India launched from Indian soil using an Indian launch vehicle, SLV3?

Rohini Satellite (RSI).

323

What are bacteria? Where are they found?

Bacteria formerly classified as plants are now classified separately as Prokaryotes. They are so small that we can see them only with a microscope. They are found almost everywhere. Bacteria cause and spread diseases, but there are many bacteria that are helpful to man. Bacteria are responsible for converting grape juice into wine and milk into curd.

324

What is the name of the instrument that records heart beat?

Cardiograph.

325

Who discovered the connection between magnetism
and electricity?

Hans Christian Oersted.

326

Who discovered the presence of neutrons in the nucleus of elements?

Physicist James Chadwick.

327

At what temperature does water become ice?

Zero degrees on the Celsius scale.

328

What do deciduous trees mean?

Trees that shed leaves in autumn are called deciduous trees.

329

The electric discharge of which fish is the most powerful?

South American Electric Eel.

330

What is the name for power generated from water?

Hydroelectricity.

331

How is sound produced?

Basically sound is produced when a vibrating body sets air molecules in motion. Musical instruments produce sounds by vibrating strings. The vibration and waves that are produced reach the ear, which passes the vibrations to the brain. To test this take a steel tumbler and tap on it with a metallic spoon. Sound is produced. Hold the edge of the tumbler between two fingers. The sound stops. This illustrates the importance of vibration in producing sound.

332

How are motion pictures made?

When the eyes see an image, they hold onto it in the form of a visual memory for a fraction of a second after it is gone. In a motion picture, the projector flashes still pictures quickly in succession. The usual numbers of pictures that are projected per second are 24. Because of persistence of vision, the picture seems to be one continuous moving picture.

333

From which part of the plant, is ginger that we eat obtained?

From the stem.

334

Who was the first person to find out that microscopic organisms are responsible for milk, wine, etc turning sour?

Louis Pasteur.

335

What is the meaning of the word Hippopotamus?

River Horse.

336

Who invented the Hovercraft?

Christopher Cockerell.

337

Who discovered Vitamins?

Christopher Eijkman - though he did not use the word, vitamin.

338

Who coined the word Vitamin?

CasimirFunk.

339

Why does the planet Mars appear red?

Due to the highly oxidised surface of the planet.

340

Name the Vitamin that prevents night blindness.

Vitamin A.

341

Where do sea plants obtain carbon dioxide to manufacture their food?

From dissolved gases

342

Who is considered as the father of modern Medicine?

Hippocrates.

343

How does an Octopus camouflage itself?

By changing its colour and merging with the background.

344

Who first proved that lightning is an electric charge coming down to the earth?

Benjamin Franklin.

345

What are cosmic rays?

Cosmic rays are radiation from outer space, which bombard the earth. They constantly strike the molecules of the earth's upper atmosphere. As a result, additional radiations are produced. The atmosphere absorbs most of these rays.

346

What is a cocoon?

It is a silk case, that covers a caterpillar before it becomes a moth (butterfly). After the caterpillar is completely wrapped in its cocoon, it sleeps through the winter.

347

What does the acronym LASER stand for?

Light Amplification by Simulated Emission of Radiation.

348

How is cement obtained?

Heating a mixture of limestone and clay.

349

Name the only mammal, other than man, that can walk upright?

Gibbon.

350

Which disease is caused by insufficiency of iodine in the diet?

Goitre.

351

What are molluscs?

A class of animals with a soft body and no bones.

352

Which animal has the longest life span?

Tortoise.

353

How is the glow of a firefly caused?

When certain proteins get oxidised, in the presence of an enzyme called luciferase, light is produced. Fireflies have special light organs on the underside of the abdomen. Here in the presence of luciferase, light is produced.

354

Who first enunciated the laws of heredity?

Gregor Johann Mendel

355

What does the acronym, SONAR, stand for?

Sound Navigation and Ranging.

356

What are comets?

Comets are heavenly bodies that travel around the sun. When they are near the sun, they look like stars with long glowing tails. Halley's comet appears once in about 76 - 78 years. Some comets appear near the sun only once in millions of years. A comet has a head, which looks like a star. The head is surrounded by a coma or a fuzzy hood. The tail may be millions of kilometres long.

357

Why does a metal rod feel cooler than a piece of wood?

Metals are good conductors of heat. When we touch a metallic rod, it takes away the heat from the hand and feels cooler. A piece of wood is a bad conductor of heat and therefore it does not take away the heat from our hands.

358

Why does a jet of water come out of a whale's back?

It is air, exhaled by the whale.

359

How many teeth do sheep have on their upper jaw?

None.

360

How are helicopters useful in rescue operations?

A helicopter can move up, take off or land easily from small clear areas. Hence they are useful in dropping food or rescuing stranded people. It has a rotor, which enables it to rise up or go down, vertically.

361

How can lizards walk on walls?

The base of their paws has cuplike structures that stick to the walls. This enables them to move even on walls.

362

How does a perfume spread to the corners of any room even though there is no breeze?

Molecules of oxygen, nitrogen and other gases in the air keep on spreading all around them.

363

Where does light fall inside the eye?

Retina.

364

Chlorine is very injurious to health. So is sodium. The table salt we use is sodium chloride. Why is it not dangerous to health?

It must be noted that a compound formed from two or more elements need not have a single property of its constituent elements. Sodium and Chlorine combine to form table salt, which is healthy (in small amounts). Water, which sustains life, is formed from hydrogen and oxygen. The properties of hydrogen as well as oxygen are not found in water.

365

How does a frog breathe under water?

Through its skin.

366

What is the difference between a tortoise and a turtle?

Tortoise is the name applied to the terrestrial species and turtle is the name applied to the aquatic species.

367

What is meant by sublimation in chemistry?

Conversion of a substance from solid state to vapour state (without the intervening liquid state) is sublimation. For example, iodine sublimates from its solid state to vapour.

368

What are the sieve like plates in a whale's mouth called?

Baleens.

369

Why do people cover ice slabs with sawdust?

Sawdust is a bad conductor of heat and slows down the melting of ice.

370

Why are droplets formed on the outer surface of a glass when cold water is poured into it?

The moisture in the air condenses on the cool outer surface of the glass.

371

Why is food preserved in a refrigerator?

Most bacteria are destroyed as the temperature of the surroundings rises. Temperatures higher than 40° C do not favour growth of bacteria. Similarly low temperatures prevent bacteria from multiplying. Hence food is preserved in the refrigerator by keeping its contents at low temperature.

372

Why do we feel sleepy after a heavy meal?

The blood circulation to the digestive tract increases. As a result the blood circulation to the brain is reduced. This makes us sleepy.

373

Which organs in the human body filter waste products from the blood?

Kidneys.

374

Which organs are most damaged when a person consumes much liquor?

Liver and stomach.

375

What does Aurora mean?

Bright patches of light are seen at high latitudes above 60° north or south. They are named Aurora Borealis (northern lights) or Aurora Australis (southern lights) depending on their position. The term "Aurora Polaris", polar lights, is a general name for both. The aurora consists of rapidly shifting patches and dancing columns of light of various hues.

376

Which vitamins are soluble in water?

Vitamins of the B and C group.

377

What is the composition of perspiration?

Mostly water with a little salt.

378

Which gland in the human body produces insulin?

Pancreas.

379

What is the principal enzyme in the gastric juice?

Pepsin.

380

What is the vaccination given to prevent polio?

Salk Vaccine. It was discovered by Jonas Edward Salk in 1952. The theory behind the Salk Vaccine is that a virus that has been killed cannot infect or multiply, but it can still produce antibodies against that particular virus. The vaccine was tested first on monkeys and eventually on children, including Dr. Safk's three children, before it was released for nationwide distribution.

381

What are Pachyderms?

Animals with thick skin like elephants and rhinoceros.

382

Why is it that some people have a dark skin?

The dark colour of the skin is due to a pigment called melanin. On exposure to sunlight, man's skin undergoes gradual tanning to protect the skin from injurious solar rays.

383

Which Vitamin helps in preventing rickets?

Vitamin-D.

384

Which is the second most common element on the
earth's surface?

Silicon.

385

Which planet is known as the red planet?

Mars.

386

What does a lizard do when its life is in danger?

The lizard discards its tail to divert the attention of its enemy.

387

Why is the housefly considered a health hazard?

On their legs they may carry millions of germs. When they rest on a food plate, these may be transferred to the object they rest on.

388

Which metal is also called quicksilver?

Mercury.

389

What is the main food of a Koala bear?

Eucalyptus leaves.

390

If hair is dead tissue, how does it grow?

It is true that hair consists of Keratin, a dead tissue. But the hair is lodged in a follicle located a little below the scalp, which is very much alive. This is where the growth takes place. The living hair pushes up the dead tissue. That living tissue also dies and is pushed up. Pull out a hair and you will feel pain and understand the truth of this statement.

391

What is meant by Acid Rain?

When there is a substantial amount of sulphur dioxide, carbon dioxide, etc in the rain, it is referrec to as acid rain.

392

What is the common food of the Blue Whale?

A shrimp like creature called krill.

393

What is Betelgeuse?

It is one of the brightest stars visible in the night sky, It is in the constellation, Orion. It is also called Alpha Orionis, It takes about 300 years for the light from Betelgeuse to reach the earth.

394

How long do elephants live?

65 to 100 years.

395

What do a koala bear, opossum, wombat and bandicoot have in common?

They are all Marsupials, i.e. they carry their young ones in pouches.

396

Name the person who first discovered the presence of Microbes.

Anton Van Leeuwenhoek.

397

How do mother animals recognize their babies?

By their smell.

398

Why do water pipes burst in hill stations?

There is an unusual expansion of water, when its temperature goes below 4° C. Instead of contracting, the water begins to expand till ice is formed at zero degrees Celsius. Unable to bear the pressure, the pipe bursts.

399

Which animal shoots its quill and hurts the enemy?

Porcupine.

400

Who made the first electric motor?

Michael Faraday.

401

Who first used electrolysis for isolating elements?

Sir Humphry Davy.

402

Who first put forward the Atomic Theory that all matter is made of atoms, held together by some force of attraction?

John Dalton.

403

Is it true that the age of a tree can be known by studying its rings?

Yes, each year during spring a light ring grows just inside the bark of the tree. During summer and autumn, the ring that grows is darker. Too little sunlight, too little moisture or injury results in a smaller and darker ring. After counting the rings, we can assess the age of the tree.

404

How does the rotation and revolution of the earth affect our lives?

The earth rotates on its axis even while it revolves around the sun. The rotation results in night and day. As the earth revolves around the sun, it also tilts on its axis. This tilt causes changes in the earth's position, which results in the seasons.

405

Who found out that oxygen is present in both water and air?

Antoine Lavoisier.

406

Which Vitamin is important for the health of bones?

Vitamin D.

407

Why do animals like rats and squirrels keep gnawing at things?

Gnawing helps wear down their teeth. If they did not gnaw at things their teeth would keep on growing.

408

Who was the first woman of Indian origin to travel in a space vehicle?

Kalpana Chawla.

409

Why does a snake flick its tongue so often?

To smell the surroundings.

410

What is the scientific name for man?

Homo Sapien.

411

Who is considered to be the father of modern experimental science?

Galileo Galilei.

412

What is the name of our galaxy?

Milky Way.

413

How is petroleum formed?

Remains of plants and tiny animals that lived millions of years ago remain buried and turn into petroleum.

414

What is a mirage? How is it caused?

A mirage is a reflection, caused by the bending of light rays. When we ride along highways particularly in arid regions, we see a reflection ahead, which looks like water. This is caused by a dense layer of warm air near the surface of the earth. Light rays from the sky are reflected toward one's line of vision - what one sees is a reflection of the sky and not water.

415

How is oxygen formed in the atmosphere?

In the presence of chlorophyll, a chemical reaction takes place in the leaves using carbon dioxide in the air and water transported from the roots. As a result of the chemical reaction, starch is produced. Oxygen is the by-product of this reaction.

416

Which is the juice secreted in die liver which helps digestion?

Bile.

417

What is meant by the word 'frequency' of a sound?

Frequency is defined as the number of vibrations per second. It must be noted that sound is caused as a result of vibrations in air columns or strings or objects. Sound travels in waves.

418

Which is the longest poisonous snake in die world?

King Cobra

419

What is the tendency of plants to grow towards sunlight called?

Phototropism.

420

Why do snakes shed their skin?

Unlike human beings, whose growth stops around 20 years, snakes keep on growing. This becomes possible because they keep casting off old skin and develop new skin, when the old one is shed.

421

Why does it take longer to cook food at high altitudes?

The atmospheric pressure at high altitudes is much lower than at sea level. The greater the pressure, the faster the cooking.

422

What is the use of the ozone layer in the earth's atmosphere?

It bounces off ultraviolet radiation.

423

How do we get heat and light from the sun?

Through radiation.

424

How do insects breathe?

Insects breathe through the tiny holes in their body.

425

Why doesn't ice sink in water?

Ice is lighter than water. After the temperature of water cools down to 4° Celsius (instead of contracting) water keeps on expanding till it reaches 0° Celsius and becomes ice.

426

Apart from earth on which other planet in the solar system does life exist?

Nowhere else. As we know it.

427

What is meant by the Water Table?

Water filters down the surface of the ground and is absorbed and stored by soil and rocks in a zone of saturation. The top of this zone is called Water Table. During drought, the Water Table too goes down.

428

Who is known as the father of computers?

Charles Babbage.

429

Why do we feel hungrier in winter?

In winter we need energy to maintain the body temperature in addition to sustaining normal activities of the body. To meet this requirement of energy we eat more.

430

Can you give ah example of reflex action?

Knee jerk. It is the involuntary kick caused by a blow on the tendon just below the knee.

431

What is an electrocardiograph?

The electrocardiograph is an electrical instrument, which records the activity of the heart muscle. As the heart beats, several activities take place in a regular! order. The electrocardiograph records changes that occur in a regular order, during a complete heartbeat.

432

Which bird can rotate its head by 180 degrees on either side?

The Owl.

433

Man, dogs, cats, horses have lungs through which they breathe. How do smaller animals like fish, earthworm, etc obtain their requirement of oxygen?

Earthworms also respire. They use their moist skin to exchange carbon dioxide for oxygen. The fishes use their gills to respire. Even frogs in the tadpole stage use their skin for respiring. Reptiles such as snakes and turtles and even birds breathe through lungs.

434

What are the uses of snake venom?

It is helpful in curing many ailments affecting the nervous system.

435

What is the major element a star is made of?

Hydrogen

436

Where does a female butterfly lay its eggs?

Under side of leaves.

437

Who invented the miner's safety camp?

Sir Humphry Davy.

438

Name the world's largest rodent and where is it found.

Capybara found in the Amazon jungles of South America.

439

What is the chemical name of baking soda?

Sodium Bicarbonate.

440

What is Telepathy?

Telepathy is direct communication of thought from one person to another, without using any physical channels of communication. Though there are many who claim telepathy is possible, there has been no positive proof of the existence of telepathy.

441

What is ultrasound?

Human beings cannot hear sound waves which have frequencies above 20,000 vibrations per second. This is termed ultrasound.

442

Who was the scientist who initiated the Atomic Energy Programme of India?

Homi Bhabha.

443

Who invented the rigid airship?

Ferdinand Von Zeppelin.

444

Who invented the calculator?

Blaise Pascal.

445

From which element was the first Atom Bomb made?

Uranium 235.

446

Who invented the diesel engine?

Rudolf Diesel.

447

Who made the first locomotive that had successful
runs?

George Stephenson.

448

What is paper made of?

Mainly wood pulp.

449

Name the Chinese method of curing ailments by using needles?

Acupuncture.

450

What causes rusting? How can it be prevented?

Metals like iron are often exposed to moisture. Rusting is the process of oxidation occurring when the iron and air slowly combine to form iron oxides. Oil is often used to slow down rusting. When a coat of paint or varnish is given to a metal, this also prevents (reduces) oxidation.

451

What is Googol?

Googol is the number one followed by a hundred zeros.

452

Which are the only mammals that can see colours?

Man and monkey (apes). It is commonly believed that bulls react violently when they see a red rag. Bulls just cannot see any colour. They react to the teasing movement of the rag.

453

Why does an apple that has been cut open turn brown and then black?

Polypnenols in the apple get oxidised.

454

Why does the liquid in the egg become solid when heated or boiled?

Due to congealing - coagulation of the yolk.

455

What is the green colour of the leaf due to?

Chlorophyll.

456

How many days does Mercury take to complete one rotation on its axis?

59 earth days.

457

What are aerial roots?

Roots that grow down from the branch of a tree. The banyan tree is a good example.

458

What is Halley's comet?

The Halley's comet is named after the English astronomer Edmund Halley. The theory of gravitation developed by Isaac Newton helped Halley to discover that the bright comet that appeared in 1682 had an orbit that brought it back to the inner solar system at regular intervals.

459

Why is helium used in gas balloons?

Because helium is very light and does not burn.

460

What is plastic surgery?

Plastic surgery is surgery performed on someone's face or body to remove a deformity or to make it more attractive.

461

How can the moon which is very small, cover the sun which is very big, during an eclipse?

The sun is far far away compared to the moon, Therefore even though the sun is very large, the moon can cover it. Even a coin can cover the moon, if held close to the eye.

462

What is the Archimedes Principle?

It is a law of physics that states that when an object is totally or partially immersed in a fluid, it experiences an upward thrust equal to the weight of the fluid displaced. The principle is most frequently applied to the behaviour of objects in water, and helps to explain floating and sinking and why objects seem lighter in water.

463

What is meant by a refracting telescope?

A refracting telescope is made by using two lenses, both of which are convex.

464

What are corals?

They are combined skeletons of tiny marine animals, which live together in a colony.

465

What is the distance between the earth and the sun?

About 150 million kilometres.

466

Why does water in an earthen pot become very cool in summer?

Earthem pots have tiny holes from which water seaps out to the surface. When this water evaporates, it takes away the latent heat of vaporisation and keeps the pot {and its contents) cool.

467

Why do dogs pant?

To keep themselves cool. When they throw out the tongue while panting, the moisture in the tongue evaporates. This directly results in cooling. Humans keep themselves cool by sweating and then evaporation of the sweat, from a large surface of the skin.

468

Which important mineral is to be found in spinach?

Iron.

469

What does milking of poisonous snakes mean?

It means drawing out poison from the serpents for medical use.

470

Who first isolated Sodium?

Sir Humphry Davy.

471

What is a robot?

Robot is any machine, developed by man to do the work of a human being such as running a machinery by remote control or to operate devices like switch boards automatically. It is usually directed by sound waves, light waves or radio waves.

472

What is moulting?

Moulting takes place because of a number of reasons. Birds discard old feathers for new ones. This is also referred to as moulting. Snakes keep on growing, unlike human beings whose growth stops after attaining adulthood. The snakes discard their skins for a new one. Lobsters, crabs, etc have a hard covering outside the body to support. The animal then breaks out of the old cover and quickly grows before the new chitin already recreated by die tissues underneadi, can harden. Frequently during such periods, the animal hides, since it has no protection then.

473

In which organ of the human body are the lymphocyte cells manufactured?

Spleen.

474

Which are the distinct layers of the skin?

Dermis and Epidermis.

475

Who invented the printing machine?

Johan Gutenburg.

476

Who pioneered the use of antiseptic?

Joseph Lister.

477

What is the name of the gland that produces tears?

Lachrymal Gland.

478

What is the name of the bacteria that converts milk into curd?

Lactobacillus.

479

What does DPT stand for?

Diphtheria, Pertussis and Tetanus. DPT is a combined vaccine for diphtheria, whooping cough and tetanus.

480

What does a Hydrometer measure?

Density of liquids.

481

Why is the rainbow seen only during and after the rain?

This is so because the rain drops serve like prisms and diffract the white light of the sun into violet, indigo, blue, green, yellow, orange and red colours.

482

What is meant by a radio telescope?

From their telescopes, astronomers could study objects in outer space that could not be seen with the naked eye. Radio telescopes are telescopes that can study long waves, which are not visible. They can do this using antenna, since radio waves are much longer than light waves. To be effective, radio telescope needs to be much larger than ordinary optical telescope,

483

What is smog?

Smog is a mixture of solid and liquid fog and smoke particles. Fog is formed when the humidity is high. The word smog is derived from smoke + fog.

484

What is the name of the layer in the atmosphere of the earth that protects the earth from harmful radiation?

The ozone layer.

485

What is the name of the radiation that comes from
outer space?

Cosmic Rays.

486

For the protection against which disease is the B.C.G vaccination given?

Tuberculosis (T.B)

487

What are Sunspots?

Areas where the sun's surface is slightly cooler than normal - about 4000 degree C instead of 6000 degrees C.

488

What is the scientific name for Vitamin C ?

Ascorbic Acid.

489

Name the galaxy that is nearest to our galaxy.

Andromeda Galaxy.

490

Who invented the Barometer?

Evangelista Torricelli.

491

Tn the human body what is the end product of protein
digestion?

Amino acids.

492

Who gave the name rubber to the gum of the Hevea
tree?

Joseph Priestley. Because the gum could rub oui pencil marks.

493

What are salivary glands?

Salivary glands are located in the mouth. There are three pairs, one pair is located in front of the ears, one pair is located underneath the lower jaw and the third is under the tongue. Salivary glands secrete an enzyme called ptyalin, which helps in the digestion of starches. Saliva has an alkaline action. If you see many players chewing gum, it is because when a person is tense, the stomach produces more acids. The saliva, produced by chewing gum, neutralizes this acid.

494

Why do crocodiles shed tears?

They secrete the excess salt in die body through this action. They get rid of this by means of a gland near the comer of the eyes.

495

What is Bronze?

An alloy of copper and tin.

496

What is the meaning of the word "DINOSAUR"?

Terrible lizard.

497

What is Brass?

An alloy of Copper and Zinc.

498

Which element is important for the health of bones?

Calcium.

499

Which Vitamin helps in preventing rickets?

Vitamin D.

500

What is the name for the position of the moon, an earth satellite, when it is at the greatest distance from the earth?

Apogee.

501

What is the study of weather and climate called?

Meteorology.

502

Name the unit in which electric current is measured?

Ampere.

503

What are the four stages in the development of a butterfly?

a) Egg
b) Larva
c) Pupa
d) Butterfly

504

Who invented the Radio?

G. Marconi.

505

What is meant by Hibernation?

Many animals sleep or go into a trance-like state during the long, winter months. This winter sleep is called hibernation. Polar bears go into hibernation in winter.

506

What is meant by Escape Velocity?

It is the minimum initial velocity required for an object to escape the gravitational attraction of an astronomical body, and to continue travelling away from it without the use of further effort.

507

Which present day animals are said to be direct descendants of dinosaurs?

Komodo dragon and Crocodile.

508

Who invented the military tank?

Ernest Swinton of Britain.

509

What is the study of birds called?

Ornithology.

510

Who was the founder of the system of medicine known as Homoeopathy?

Samuel Hahnemann.

511

From which ore is Aluminium made?

Bauxite.

512

How does a plant transfer nutrients it absorbs through its roots to other parts?

Through tiny tubes called Xylem.

513

Who discovered the planet Uranus?

William Herschel.

514

Kidneys help the body to eliminate waste. Which other parts of the human body do the same?

Lungs, skin and rectum.

515

Why is a soap bubble always spherical and not a square or a triangle?

When a soap bubble forms and goes up in the air, it is subject to immense pressure from all sides. Only a spherical shape can withstand maximum pressure. That is why soap bubbles are always spherical.

516

Who discovered the circulation of blood in the human body?

William Harvey, in 1628. People did not believe in what Harvey said and they opposed his ideas. It took many years for the opposition to die down.

517

What is meant by centrifugal and centripetal force?

If a ball is whirled at the end of a string in a circular motion, it would seem as if the ball were suddenly very heavy and pulling harder as it is whirled faster. The force of the string pulling the ball toward the centre is the centripetal force. There is an outward force on the string by the ball. This outward force is the centrifugal force.

518

How much blood does an average adult human being have?

About 6.5 litres.

519

Who wrote the book on "The Origin of species by means of Natural Selection"?

Charles Darwin.

520

Which is the most destructive insect in the world?

Desert Locust.

521

Who invented the sewing machine?

EliasHoweofUSAin 1845.

522

What are the substances that can cause cancer called?

Carcinogens.

523

What is meant by Photosynthesis?

Photosynthesis is the word used for making food from carbon dioxide in the air and water from the soil, in the presence of sunlight. It occurs in plants.

524

What is meant by colour blindness?

Inability to distinguish one or more of the primary colours.

525

Who discovered the Laws of Motion?

Sir Isaac Newton,

526

Who invented the Telegraph?

Samuel Morse.

527

What is a Supernova?

A star, which suddenly burns up a lot of its matter and gives a brilliant light.

528

How many chromosomes does a man have in his body cell?

46.

529

Why is selenium used in the making of photoelectric cells?

Photoelectric cells convert light into electricity. Selenium is used in making diese cells because its electrical conductivity increases when light strikes it and because it can convert light into electricity.

530

For which invention or process is Henry Bessemer best known?

Bessemer converter used for making steel.

531

Who was the first man to study sunspots?

A German by name Hienrich Schwabe.

532

Mercury is closest to the sun, then how come Venus is the hottest planet?

Venus has thick clouds around it that prevent heat from escaping from its surface.

533

Which planet rotates the most slowly on its axis?

Venus

534

How does a microwave oven work?

Water molecules vibrate and rub against each other, producing heat because heat is produced by diese molecules an external source of heat is not required for cooking in a microwave.

535

Who produced the world's first petrol driven car?

KarlBenz.

536

Why does the running sound of a train change when it passes over a bridge?

Sound travels in the form of waves. The frequency of the waves and die amplitude (the width) of the waves determine the sound. The sound waves are of different kinds, when a train moves on solid ground, and when it moves on a bridge, whether made of steel or plain concrete.

537

What is a photometer?

An instrument for measuring the intensity of light.

538

What is meant by Radio carbon dating?

Scientists describe the radioactivity of an element in terms of half-life - the time the element takes to lose half of its radioactivity through decay. By measuring the radioactivity scientists can calculate the age of the element that is being tested.

539

What is the meaning of geothermal energy?

The heat produced witiiin the crust and upper mantle of the earth, primarily by decay of radioactive elements.

540

What is the difference between nuclear fission and nuclear fusion?

The reaction where heat is produced because of the fission (division) of a nucleus is called nuclear fission. The reaction in which heat is produced because of the fusion of two nuclei is called nuclear fission. In hydrogen bomb die reaction was due to nuclear fusion. In the atomic bomb dropped on Hiroshima and Nagasaki, it was a fusion bomb.

541

What is Robert Boyle known for?

Boyle is known for his experiments on the physical properties of air and his law on the relationship between the pressure and the volume of the gas.

542

What is genetics?

Genetics is the study of all those qualities of organisms that are governed by certain biologically active elements derived from the parents.

543

How many toes does an ostrich have on each of its
legs?

An ostrich has two toes in each leg.

544

Who is considered to be the father of modern astronomy?

Copernicus.

545

From which material is aluminum made?

Bauxite.

546

What are asteroids?

Asteroid means "like star". Asteroids are heavenly bodies like the earth, but very much smaller in size. Some may be only a kilometre or two in diameter. They also orbit around the sun.

547

What is meant by convection of heat?

A process in which heat is transferred by movement of heated fluid such as air and water is called convection.

548

What is meant by cloud seeding?

Spraying of certain chemicals into clouds to induce rain.

549

Who was the first man to point out that things get spoiled because of germs?

Loius Pasteur.

550

Why does cutting onions give a burning sensation in the eyes?

When onions are cut, volatile oils, containing sulphur, are released. In combination with the water in the eye, they produce irritation.

551

What is the enzyme in human saliva?

Mainly Amylase, which converts starches anc glycogen into the sugar maltose. Apart from saliva amylases are found in pancreatic juices and intestinal juices too.

552

What is meant by ignition point?

Ignition occurs when the temperature of a substance is raised to die point at which its molecules will read spontaneously with oxygen, and the substance begin; to bum. This is called the ignition point.

553

Which is the largest and heaviest snake in the world?

The anaconda. It weighs upto 200 kg.

554

To which family of plants do bamboos belong?

The grass family.

555

Who propounded the theory of relativity?

Albert Einstein.

556

How does the chameleon catch its prey?

It flicks out its long sticky tongue and catches unwary insects flying by.

557

What is concrete? How is it made?

Concrete is a rock like substance made from cement, natural sand, stone and water. Cement and water react chemically and serve like glue to bond the stones and form a hardened mass. When the material is still in a "plastic state" it can be very easily formed into various shapes. But once the concrete sets (hardens) no changes can be made.

558

In which part of their body do spiders spin the thread?

Abdomen.

559

What is meant by fermentation?

Breakdown of organic substances into simpler substances due to the action of bacteria is called fermentation. Grapes are fermented to produce wine. Thus fermentation of wheat and rice results in the breakdown of the starches to simpler sugars and alcohols.

560

In which part of the plant are ovules contained?

Pistil.

561

How long do butterflies live?

2 to 3 weeks.

562

What is the study of prehistoric animal and plant life through the analysis of fossils called?

Palaeontology.

563

What does mammal mean?

A mammal is a warm-blooded animal, which suckles its young ones with milk and has hair on its skin.

564

Which are the main gases in the atmosphere of the earth?

Nitrogen and oxygen.

565

Who invented the stethoscope?

Laennec.

566

What is a huge mass of ice slowly moving ahead called?

Glacier.

567

What is an ammeter used for?

Measuring the strength of an electric current.

568

How do bats communicate with each other?

Bats produce screeching sounds. As these sounds strike objects around them, they produce echoes, which are heard by the bats. This helps the bats in navigation. Human beings cannot hear the sounds produced by the bats as they have much higher frequency than the audible range of the human ear.

569

What are the three main constituents of a galvanic cell?

a. An anode
b. A Cathode
c. An electrolyte in which the anode and cathode    are placed.

570

Who invented the telephone?

Alexander Graham Bell. He was, however, interested in constructing an electrical device that would help deaf-mutes learn to speak.

571

What is the fluid part of the blood called?

Plasma. It is about 90% water.

572

What is malaria?

Malaria is an acute disease caused by an animal parasite called plasmodium. The disease is spread by the bite of the female Anopheles mosquito.

573

What is the origin of the word 'Malaria' ?

Romans were familiar with this disease. They thought it is caused by bad (mal) air (aria).

574

How many eggs does a starfish lay at a time?

Millions.

575

What does the acronym RADAR mean?

Radio Detection and Ranging.

576

What is meant by Diabetes?

Diabetes is caused because of inadequate secretion of insulin by the pancreas or the inability of the body to utilise the insulin produced.

577

How does the sun generate its energy?

Inside the sun a reaction similar to that of a hydrogen bomb goes on continuously. Two atoms of hydrogen fuse to produce an atom of helium. The sun is today at the midway of its life.

578

What is the meaning of the word 'Protozoa' ?

Protozoa means the first animal. They are the simplest form of life. They are made of a single cell.

579

What is the difference between dyes and pigments?

Dyes are complex organic substances that are chemically bound to the fibres. Pigments consist of larger particles that form a film on the surface.

580

Who proposed the Centigrade Scale?

Anders Celsius first proposed the centigrade thermometer, which has a scale of 100 degrees separating the boiling and freezing points of water.

581

Why do flocks of swans fly in a V-formation?

By flying in this way they meet minimum resistance from the air to their flying.

582

Which is the fastest moving land snake?

The Black Mamba, which has a speed of about 11 km per hour.

583

What is meant by the term habitat?

Habitat is the place where a certain animal or plant would live and grow naturally. Thus an ocean is the habitat of whales and a pond is the habitat of frogs.

584

How can astronauts walk in space without any support to walk on?

Because there is hardly any gravity far away from the earth. (Or any heavenly body).

585

Who is usually considered to be the discoverer of oxygen?

Joseph Priestley.

586

What is a Tapir? Where is it found?

A Tapir is an animal that looks like a pig. It is found in Malaysia and Central and South America.

587

Why are tea plants cut when they grow to a height of two metres or more?

To force more tender leaves to branch out and make handpicking of leaves easier.

588

What is forging?

The shaping of metals by hammering them is called forging.

589

What was Chandrasekhar Subrahmanyan known for?

Indian-born American theoretical astrophysicist and Nobel laureate, Chandrasekhar Subrahmanyan contributed greatly to our understanding of the evolution of stars. Chandrasekhar was best known for his theoretical prediction, made at the age of 20, that large stars would collapse at the end of their lives into some unknown state even more dense than that of a white dwarf.

590

What is the condition caused by lack of Vitamin C?

Scurvy.s

591

Who was the first man to make a phonograph (gramophone)?

Thomas Alva Edison.

592

What is a black hole?

A body whose mass is so intensely concentrated that even light cannot escape its gravitational attraction. Normal properties of space in its vicinity are altered drastically.

593

How did Charles Goodyear discover the vulcanisation of rubber?

Accidentally he spilled a mixture of rubber and sulphur on a hot stove. He observed that the rubber had become stronger and elastic. From there he got; the idea of hardening rubber.

594

How did Roentgen discover X-rays?

While experimenting with a glass tube from which the air had been pumped, Roentgen happened to pass an electric current through the tube. Nearby was a screen coated with Barium Platinocyanide. Suddenly he noticed that the screen was glowing with a greenish blue light. After experimenting with this radiation, coming from the evacuated glass tube Roentgen found that this radiation could pass through substances of varying densities placed between the tube and the screen. He named these rays X-rays.

595

What are chromosomes?

Chromosomes are tiny thread-like parts of a cell. These can be seen under a microscope. They are made up of smaller parts called genes. These chromosomes and genes decide heredity.

596

Who was the first person to show that the Milky Way is composed of stars?

Galileo Galilei.

597

What is the average life of a red blood corpuscle?

120 days.

598

What is the scientific study of insects called?

Entomology.

599

What are the properties of aluminium, which make it very useful, particularly in the aerospace industry?

Aluminium is very light and yet very strong. It does not get corroded. Aluminium's excellent electrical conductivity makes it very useful in making high voltage electrical conductors.

600

Who invented the Battery?

Alessandro Volta.

601

Name the first aircraft to hard land on the moon.

Luna 2. It was launched on September 12, 1959 by the USSR.

602

Name two countries, which use geothermal heat (heat from far below the earth's surface) to produce electricity?

Italy, Iceland, Japan, New Zealand, USA and Russia.

603

What is cerebrum?

The cerebrum is the main part of the brain and controls the ability to think. The cerebrum receives impulses and directs the body into activity.

604

What are citrus fruits?

Citrus fruits are those, which contain citric acid in sizeable amounts. Citric acid gives the citrus fruits their sour taste. Lemons, oranges and limes all contain citric acid.

605

What is the difference between an Arabian camel and a Bactrian camel?

The Arabian camel (or dromedary) has only one hump, while the Bactrian camel has two humps.

606

What is carbolic acid?

The scientific name for carbolic acid is Phenol. It is extremely poisonous. It is used in the preparation of some plastics. Picric Acid, obtained from phenol, is an ingredient in many explosives.

607

What is meant by a Marsupial?

Animals carrying their young ones in a pouch.

608

What is the only food of the giant pandas in the wild?

Bamboo shoots and leaves.

609

What is the name for the unit of electric power?

Watt.

610

What causes tides in the ocean and sea?

Gravitational pull of the moon and to some extent the sun.

611

Why does a fire look yellowish, at times?

When the combustion (burning) is not complete the colour of fire becomes yellowish. When the combustion is complete, the colour changes to pale blue.

612

Which material is used to make cellophane?

Cellulose, the chemical substance that lines the walls of plant cells. Cellophane is used in packaging.

613

What is a cataract?

Cataract is a disease affecting the lens of the eye. The lens consists of a semi-solid substance, enclosed in a capsule. Cataract is a condition in which the lens loses its transparency and tends to become opaque.

614

What is the difference between mass and weight?

Weight and mass are two different things. The amount of matter that a body contains is mass whereas the weight of an object will be a little less near the equator (where it is further away from the centre of the earth) and a little more at the poles. An object in free space has no weight, but it will have a definite mass.

615

What is meant by a catalyst?

A catalyst is a substance, which alters the rate of speed of a chemical reaction, without itself being permanently changed. Normally a catalyst hastens or encourages the rate of reaction. However, at times, catalysts are used to slow down a reaction.

616

Who discovered Penicillin?

Alexander Fleming

617

What is measured in the Richter scale?

Earthquakes.

618

When was the metric system introduced?

During the French revolution, France introduced the metric system. The standard of length was related to the dimensions of the earth rather than the dimensions of a human limb.

619

Where would you find a dodo?

Nowhere. It was last reported in Mauritius in 1681. Now it is extinct.

620

When did Marie Curie win the Nobel Prize?

In 1903 for physics and in 1911 for chemistry.

621

Of all the bones in the skull and the face, which is the only movable bone in human beings?

The lower jaw.

622

How big is the Milky Way?

It is estimated that the Milky Way has over a hundred billion stars. The sun is one of the stars in the Milky Way.

623

Where does the impure blood enter the human heart?

It enters the cavity of the right auricle through two veins - one called the superior vena cava enters from the head region and die other called the inferior vena cava enters from the lower or posterior region of the body.

624

What is the difference between Direct Current and Alternating Current?

The current flowing in a circuit is described as direct current if it flows continuously in a single direction, and as alternating current if it flows alternately in each direction.

625

What is distillation?

Distillation is the process of converting a liquid into vapour form (by heating) and then cooling this vapour to recover the evaporated constituents by the process of condensation.

626

How does a thermos flask retain die heat of its contents?

It has a tightly fitting cap of cork or such material, which is a poor conductor of heat. The bottle has a double layer of glass. Glass too is a poor conductor. There is vacuum between the layers of glass to prevent loss of heat by convection and conduction. If the surfaces are made highly reflective, even radiation can be reduced.

627

Who made the first balloon that could fly?

Joseph & Jacques Montgolfier.

628

How are mosquito fish helpful to man?

They eat mosquitoes.

629

What is meant by the Hippocratic oath?

Hippocrates was a Greek physician whose oath is still taken by medical students, when they graduate. The oath reads, in part, "I swear so far as power and discernment shall be mine, I'll carry out regimen for the benefit of the sick and will keep them from harm and wrong. To none will I give a deadly drug even if solicited. Into whatsoever house I shall enter I'll go for the benefit of their sick" There is also a clause that secrecy will be maintained about the ailment of the patients.

630

Name the animal, which has the largest eyes in the world.

The Atlantic Giant Squid. The diameter of its eye is about 30 cm.

631

What is horticulture?

Horticulture is the science and art of growing fruits, vegetables, flowers or ornamental plants.

632

What is a hygrometer?

A hygrometer is one of the instruments used to measure the moisture in the air.

633

What is an Ibex? Where are they found?

The Ibex is a mountain goat. It was close to extinction in the Alps. It is now under Government protection. In India Ibex is found at high altitudes in Kashmir.

634

What is inertia?

Inertia is the property of matter, which keeps a body at rest unless a force is exerted on it. Inertia also keeps a moving body in motion at the same speed and in the same direction unless a force is applied to stop this forward motion.

635

Who discovered the laws of planetary motion?

Johannes Kepler - Sir Isaac Newton later used these laws as the basis of his law of Universal Gravitation.

636

What is hybridisation?

Hybridisation is the mating or crossing of two parents of different species or varieties. Thus a mule is a hybrid of a horse and an ass. In the case of flowers, hybridisation is done by taking pollen from one plant and dusting it on the pistils of another plant. A bag is placed over the pistils until the seeds are developed. Then the seeds are planted and a hybrid is formed.

637

Who discovered the germ, which causes tuberculosis?

Robert Koch, a famous German physician.

638

What is an antidote?

A remedy for poisoning is called antidote. The remedy may consist of 
(a) Neutralising the poison
(c) Preventing the body from absorbing it or
(d) Assisting the body in eliminating.

639

What is a desert?

A desert is a large area of land that is too dry to support life. Deserts are not always hot, dry or sandy. The tundras of Siberia (in Russia) are deserts. Water is frozen here and does not support life.

640

Who invented the dynamo?

Michael Faraday.

641

Why is the Egyptian plover bird popularly called the "crocodile bird"?

The Egyptian plover bird has been nicknamed the crocodile bird following an account by Herodotus that he saw these birds enter the open jaws of crocodiles and pick pieces of food from their gums.

642

Which were the first passengers to fly in a balloon?

A sheep, a cock & a duck.

643

Which was the first living being to enter space?

A dog named Laika.

644

What is a light year?

In measuring distances on earth we use units like miles and kilometres. But even for giving the distance between the sun and the earth, we have to write 93,000,000 million miles or 150,000,000 kilometres. To write the distance between Alpha Centauri and earth we have to write long numbers. Hence measuring in units based on the speed of light has been adopted. In this scale the sun is 8 minutes from the earth. In kilometres one light year is approximately 924 x 1013 or 9,240,000,000,000,000 kilometres. Alpha Centauri is just 4.6 light years away.

645

Which element is important in the formation of blood?

Iron.

646

Name the animal that can lift 50 times its weight.

Ant.

647

Which fish carries its eggs in its mouth?

Catfish or Cichlid fish.

648

How do fireflies produce light?

There are proteins in the body of fireflies that produce light, when they get oxidized in the presence of the enzyme, Luciferase.

649

Where in the world are wooly Mammoths found?

They are extinct and are not found anywhere. But about a million years ago, they roamed over land They were the ancestors of modern elephants.

650

In which organ of the human body are the lymphocyte cells (blood cells) manufactured?

Spleen

651

What are the constituents of stainless steel?

Stainless steel is an alloy of iron, nickel and chromium. Stainless steel making involves the removal of impurities and addition of desirable metals like chromium and nickel.

652

What is meant by the term Water cycle?

Water Cycle is the story of a raindrop, which passes through other phases to become a raindrop again. In summer the water in lakes and rivers evaporates. This water vapour is warm and is pushed up by cold air. As the warm air moves upwards air currents develop. They are called winds. When the warm air passes over mountains or when it goes high up, it cools down and condenses to water again and falls down to earth. On the surface of the earth the raindrops may join other raindrops and if the earth cannot absorb this water quickly, they form streams and rivers. And the cycle continues.

653

What is Plaster of Paris?

When gypsum is heated to 120° C it loses water and becomes a white powder. That is plaster of parts. When water is added to the powder, it hardens. It is used for plasters, moulds and models.

654

Who discovered Plutonium?

Glenn Seaborg.

655

Who was the person to first identify the proton?

Ernest Rutherford.

656

What is a planarium?

A planarium is a simple form of life, which crawls about and feeds on small animals.

657

Why does milk spill out when boiled?

When milk is heated, the water in it starts evaporating. The fat globules present in the milk get separated and float on the top as cream. On further heating, more water vapour is formed. But when it tries to escape, it gets trapped by the thick layer of cream on the top. The water vapour pushes up the layer of cream and forms a bulge, which finally bursts out, causing the spill.

658

What is the difference between a porpoise and a dolphin?

Porpoises are smaller than dolphins and they do not have beak like snouts of dolphins. Porpoises live in the shallow water of ocean bays and the mouths of rivers, while dolphins live out in the deeper waters.

659

Where is the pituitary gland situated in the body?

In the brain on its underside.

660

What is ozone?

Ozone is an isotope of oxygen with three atoms of oxygen in its molecule.

661

What is the difference between a planetarium and a telescope?

Through a telescope we can see a real but small part of the sky. On the dome of the planetarium what we see is a picture of the sky, containing the sun, the moon, the stars and planets in an artificial sky.

662

What is meant by the term 'Orbit'?

Orbit is the path of any body revolving around another body. This path can be circular or elliptical (as an ellipse).

663

Where do frogs lay their eggs?

All frogs go back to water to lay their eggs.

664

Who was Pythagoras?

He was a Greek Philosopher and mathematician who lived around 520 BC.

665

Who propounded the theory that the sun and not the earth is the centre of the Solar System?

Nicolus Copernicus (Bhaskaracharya of lllh Century A.D and Aryabhata of the fifth century A.D seem to be aware of this).

666

Who invented the lightning rod to help prevent lightning from damaging buildings and physical property?

Benjamin Franklin of USA.

667

What is an anableps?

Any of the three species of Fish, commonly referred to as four eyed fish. An anableps has the ability to see above and below the water at the same time.

668

Why is it dangerous to walk on quicksand?

Quicksand is a bed of very fine, powdery wet sand. It is a thick fluid. Once a foot is placed on quicksand, it is not easy to pull it away. The foot may slowly sink in the quicksand. Struggling to take out the foot may sink the foot further down. It is advisable to wait for help. If a man remains calm and does not move his foot, he may stop sinking.

669

What is an antiseptic?

It is a chemical used to kill germs on the skin or in the wounds. It is also used on things people handle.

670

What is a satellite?

A body that revolves around another is called a satellite. The earth and the other planets are satellites of the sun. The moon is a satellite of the earth.

671

What is Greenwich Meridian Time?

Greenwich Meridian is an imaginary north-south line on the earth's surface drawn through Greenwich near London and both geographical North Pole and South Pole. This line has been arbitrarily chosen as the 0° longitude.

672

Who for the first time in recorded history used a prism to split white light into many colours?

Sir Isaac Newton.

673

What is a fuse?

The fuse is a strip of metal (or metallic wires) that melts at a relatively low temperature. When an electric circuit carries more electric current than it is supposed to carry, the fuse melts and prevents fires.

674

What is meant by the term 'freezing point'?

The temperature at which a liquid changes to the solid state is called freezing point.

675

Who made the first printing press with moveable types?

Johannes Gutenberg of Germany in the middle of the | 15* century.

676

What is meant by wireless telegraphy?

Wireless Telegraphy originally consisted of a sending key, which opened and closed the circuit and a sounder connected by wires to the key. Whenever the circuit was complete a click sound would be heard. Thus all the letters would be represented by the sounds being produced in the right sequence.

677

Which is the largest flesh-eating animal?

Kodiak bear.

678

What is larva?

A larva is a young animal that is not fully developed but is able to move about and feed itself. It changes into an adult animal that usually looks different. This change is called metamorphosis. Tadpoles, which grow into frogs, caterpillars, which grow into butterflies, and grubs, which grow to become beetles, are all examples of larva.

679

Is it true that the Himalayas grow taller year after year?

Yes, about one mm a year. The solid layer of the earth consists of about a dozen semirigid plates. As the Indian plate moving north presses against the stationary Asian landmass, the height of the Himalayas increases. The increase is imperceptible.

680

Why doesn't a crocodile harm the plover birds that enter its mouth?

Because the plover birds enter the mouth of the crocodile and eat tit-bits found there. This helps the crocodiles to improve their oral hygiene. Therefore crocodiles do not harm the plover birds.

681

From where does the moon get its light during the night?

Earth

682

How many parts was a day divided into, in ancient India?

Eight parts, called prahars. The Hindi word 'dupahar', for noon, is derived from 'du' (two) and pahar (prahar).

683

What was special about the telescope invented by Newton?

The telescope devised by Galileo was a refracting telescope. The refracting telescope uses a large convex lens as the objective to focus light and form a real image. Another lens is used to magnify it. The reflecting telescope uses a large parabolic or concave mirror instead of the objective lens to focus light and form a real image. The images produced by these telescopes are inverted. An additional lens is used to right the image.

684

How are we protected from the ultraviolet rays of the sun?

Ultraviolet rays come from the sun. If all the ultraviolet rays emanating from the sun travelling to the earth were to reach the earth, all life on earth would be destroyed. But this does not happen, because a layer of ozone (20 to 50 km) above the earth's atmosphere absorbs the ultraviolet rays of the sun.

685

What is the meaning of the word Tanning'?

Converting raw animal skin into leather.

686

Who developed the modem concept of the element?

Antoine Lavoisier.

687

How do bees communicate?

Bees communicate the source of nectar to others by the pattern of the dance they perform.

688

Who invented the Thermos Flask?

James Dewar.

689

What were the first words to be recorded on the gramophone made by Edison?

"Mary had a little lamb."

690

Which is the hardest substance in the human body?

The enamel that covers teeth.

691

What is a bone made up of?

Two-thirds of the bone is calcium phosphate. The other one-third is gelatin.

692

What are sweat glands?

Sweat glands are located under the skin of mammals. They are coils of soft, tiny tubes. The tube ends at openings in the skin called pores. Sweat glands carry moisture and waste material to the surface of the skin. When the water is brought to the surface of the skin it evaporates there and keeps the body cool.

693

Why can't a horse sit?

They don't have knees on their hind legs.

694

What is the lead of a pencil made of?

Graphite, whose main constituent is carbon

695

Who discovered radioactivity?

A.M. Becquerel.

696

Who produced the first synthetic dye?

William Perkin.

697

Where are the lobster's teeth located?

In the stomach.

698

What is parachute? How does it work?

Parachute is nothing but a big umbrella made of a special fabric. The parachute and the person using it are subject to two forces: - 1) gravity, which brings them down and 2) the buoyant force of air, which pushes up the umbrella. If the force of the gravity is greater than the buoyancy, the parachute moves down, but very slowly. Hence men can reach the ground safely.

699

What is inoculation?

ntroduction of germs into a body to precipitate a mild form of a disease. As a result antibodies are produced, which protect the body from the invading germs.

700

What is meant by Acrophobia?

Fear of heights.

701

How many lobes does a human liver have?

Four

702

What is fog?

Fog is water vapour condensing near the surface of the earth. Fog differs from clouds in that fog is close to the earth and clouds are in the sky.

703

What is the unit used for measuring work or energy?

Foot-pound. Thus if an object weighing one pound were lifted through a distance of a foot, one footpound of work would be done.

704

How many chambers are there in a human heart?

Four. Right auricle, left auricle, right ventricle and left ventricle.

705

What is the blood condition involving an abnormal reduction in the number of red blood cells called?

Anaemia

706

How are hereditary characters transmitted from one generation to the next?

Genes are believed to be responsible for transmitting hereditary characters. Every human cell contains 23 pairs of chromosomes, which are made up of many paired particles or units called genes.

707

How are hydrocarbons produced?

Hydrocarbons consist mainly of hydrogen and carbon. They are produced from the breakdown of plants and other living beings, either by bacteria or by heat and pressure under the surface of the earth. They are also called Natural Gas.

708

What is the human body made up of, according to Hippocrates?

Blood, phlegm, yellow bile and black bile.

709

From which plants do we get potatoes? How?

Potatoes grow on potato plants. The plant stems grow under the ground and are called tubers. These are the edible parts and are called potatoes. Spanish explorers brought the potato to Europe.

710

What are glacial ages?

There have been several periods of time when much of the earth's surface became covered with ice. These different periods of time make up the glacial ages.

711

How many nephrons does a human kidney contain?

About a million.

712

What is the common unit of measurement of electric power?

Kilowatt Hour.

713

When we run very fast or work strenuously, we feel tired. What is this tiredness due to?

Lactic Acid is formed when the glycogen or sugar in the muscles is used. This makes us feel tired.

714

How are gills important to fish?

They are used for breathing air by most Fishes and certain other lungless animals.

715

What are radioactive elements?

These are elements in which protons and neutrons are not in balance. They slowly breakdown to form stable elements.

716

What are lichens?

Lichens are plants that have no flowers, roots, leaves or stems. They grow on rocks and along beaches. They live on the bark of tree on the highest mountains.

717

Whose notebooks were Filled with ideas and sketches of inventions, including designs for an airplane?

Leonardo da Vinci.

718

What is a ligament?

Ligament is a term for individual tough fibrous bands of connective tissue that support the internal organs and hold bones together at the joints.

719

What is a larynx?

The larynx is the voice box, located in the throat.

720

Who is considered as the father of modern rocketry?

Robert Mulchings and Goddard Hutchings.

721

What is Brownian movement?

That small particles of matter (molecules) are in constant motion was observed by Robert Brown through his microscope, by putting very fine powder in water. This movement of molecules is referred to as Brownian movement.

722

What is camouflage in nature?

In nature many animals resort to a number of ways to protect themselves from enemies or predators. This is called camouflage. The Polar Bear, having a white colour is an example of camouflage. Similarly zebra's colour confuses its enemy and serves as a camouflage.

723

What is the chief source of uranium and radium?

The mineral, Pitchblende.

724

Why do planes flying at great speeds leave white fumes behind?

The planes leaving fume behind are jet planes. In a basic jet engine air is compressed and forced into a chamber, where fuel is added. Here combustion (burning) takes place. The hot gases that are produced escape from the base of the engine. This pushes the aircraft forward. The white fumes that you see are the hot gases as they escape out. Since the temperature around the jet is low, the fume condenses and becomes visible.

725

Why do some people have fat legs?

The cause of filaria (elephant leg) are worms called Wuchereia bancrofti the female worm gives birth to young worms and not eggs. These young ones, called microfilaria, find the way into blood stream of their victims and from there into the lymphatic vessels. The immediate cause of filarial is a mosquito called culex.

726

What is a dehumidifier? Why is dehumidification important?

Heating, cooling, ventilation and dehumidifying are aspects of air-conditioning. It is believed that a cold climate with a low level of humidity is good for health. Even food is preserved better when the temperature and humidity are low.

727

What is meant by Quarantine?

Quarantine is the isolation of persons, animals or plants, which have been exposed to communicable diseases.

728

What is the Pythagoras theorem?

The theorem states that the square of the hypotenuse of a right-angled triangle is equal to the sum of the squares of the other two sides.

729

What are pseudopodia?

Pseudopodia are temporary extension of the body of a one-celled animal such as amoeba.

730

How is plywood made?

Plywood is made by gluing wide thin slices of wood together in order to make a strong board.

731

How many pairs of legs do crabs have?

Five pairs.

732

What is a rain gauge?

It is a device used for measuring rainfall.

733

How do planaria (flatworm) reproduce?

Planaria (plural of planarium) constrict and fragment just behind the pharynx. Both pieces then develop into complete animals.

734

What is a fungus?

A fungus is a plant without chlorophyll or true leaves, stem and root. Since they are unable to make their own food, they must live on other living or dead plants and animals. Fungi (plural of fungus) are found almost everywhere. Mushrooms are fungi.

735

What is resonance?

When an object is set into vibration with a certain pitch (frequency) any other object nearby that can vibrate at the same pitch, will start vibrating. This is referred to as resonance.

736

Where are the vocal cords located in man?

The vocal chords are located in the larynx. The larynx is a hollow muscular organ forming an air passage to the lungs.

737

What are alveoli?

The tiny air sacs in the lungs are called alveoli. It is through the walls of the alveoli that the exchange of gases takes place.

738

What is meant by embalming a body?

When a body is treated in such a way that it is preserved from decay, it is called embalming.

739

What is embryology?

Many animals begin life as a fertilised egg. These grow over a period into the form of an adult animal. The study of the changes that take place as an egg develops into an animal is the science of embryology.

740

What is an element?

An element is a substance that cannot be broken down or decomposed into smaller parts by ordinary chemical means.

741

What do elements consist of?

Positively charged protons, negatively charged electrons and neutrons, which have no charge.

742

What is electrolysis?

Electrolysis is the decomposition of a substance using electricity. For example when table salt is subjected to electrolysis, it turns into sodium and chlorine.

743

Who propounded the theory of relativity?

Albert Einstein

744

What is ecology?

Ecology is the study of plants and animals in relationship to their environment. Everything that affects plants and animals and how they are dependent upon their surroundings is the subject matter of the study of ecology.

745

Why is an earthworm also called 'a Fanners best friend'?

The earthworm is called the farmer's friend because it helps him to keep the soil rich and loose so that plants can grow. As they burrow into soft soil, they swallow some of it, which passes through their bodies and finally is left behind as castings. This is enriched material.

746

What is a mammoth?

Mammoth was an ancestor of the elephant (of the modern elephant), which is now extinct. Whole frozen mammoths have been found below the ice in Siberia.

747

What is a manometer?

It is an instrument for measuring the pressure of gases.

748

How many satellites does Mars have?

Two.

749

What is medulla oblongata?

It is the part of brain that connects with the spinal cord.

750

How many pairs of nerves are there in man that are connected to the brain?

Twelve pairs. They are called the cranial nerves.

751

Why do earth and other planets revolve around the sun?

Sun's gravitational force keeps the planets in a fixed orbit.

752

Name the unit in which electric current is measured?

Ampere.

753

Which planet in the solar system moves faster around the sun than any other planet?

Mercury.

754

What are antibiotics? How do antibiotics help in curing diseases caused by bacteria?

In nature, there are moulds and bacteria that attack other organisms in order to obtain nourishment and to reproduce. Antibiotics are chemical substances produced by organisms (usually microorganisms) that are harmful to other bacteria and life forms. If you moisten a piece of stale bread and keep it in the open, there will be a greenish growth on it a little later. That is because of the spread of a mould called Penicillium Notatum. It produces penicillin. Penicillin is a highly effective antibiotic. Most bacteria double every half an hour. Just one bacterium (singular of bacteria) becomes thousands within a few hours. An antibiotic does not permit the multiplication of bacteria. In many cases, the antibiotic does not permit even the survival of bacteria.

755

Which is the star closest to our earth, after the sun?

ProximaCentauri.

756

Who founded the school of mathematics at Alexandria in Egypt?

The Greek mathematician Euclid around 300 B.C.

757

What are the remains of animals or plants, preserved deep under the earth or in rocks, etc called?

Fossils.

758

The intensity of which insect's song gives us an indication of the temperature?

The cricket.

759

What was the name of the first Atomic Reactor built by India? Where is it?

Apsara, in Mumbai.

760

Which are the only planets to revolve clockwise around the sun?

Venus and Uranus.

761

What is the study of water with reference to its occurrence in nature known as?

Hydrology.

762

How can gargling with salt water help relieve a sore throat?

An infection of the throat spreads rapidly. Quite a few varieties of bacteria double every half an hour. Gargling with warm water does not kill these bacteria, but it prevents their growth. Temperatures of more than 40 degrees Celsius are not conducive to the growth of bacteria. Any solution which has more than eight per cent salt inhibits the growth of bacteria. Thus, if you gargle with warm salt water, it will prevent the proliferation of bacteria.

763

Why does the sound of water keep changing when a vessel is being filled under a tap?

Sound is produced by the movement of columns of air. Strike a stainless steel glass with a spoon. A sound is produced. Stop the vibration of the steel glass with your fingers. There will be no sound. When water is being filled in a vessel, sound is produced because of the movement of the column of air. This column becomes smaller and smaller as the water level rises in the vessel. Hence the sound changes.

764

What is the form in which iron is found in nature?

Iron Oxide.

765

Who invented the Dynamo?

Michael Faraday.

766

How does a cricket produce the chirping sound?

By rubbing its legs against one of its front wings.

767

What is magma made of?

Molten rocks.

768

Who first introduced the concept of molecules?

Amedeo Avogadro in the year 1811.

769

From the bark of which tree is quinine extracted?

Cinchona.

770

Where do frogs usually live in the hot season?

Buried at the bottom of ponds.

771

Who discovered Calcium?

Sir Humphry Davy.

772

Which is the most abundant metal in the earth's
crust?

Aluminium.

773

What is matter made of?

Matter is made of electrically charged protons, found in the nucleus and electrons travelling about the nucleus. In addition, there are neutrons in the nucleus with a weight similar to protons but lacking any charge.

774

Who first introduced vaccination in medical practice?

Edward Jenner.

775

Name the only two poisonous lizards in the world

The Gila Monster and the Beaded Lizard.

776

What is the scientific study of the earth's crust known as?

Geology.

777

Name the mammals that lay eggs.

Platypus and Echidna.

778

Why did Galileo come into conflict with the church?

Because he supported the Copernican theory that the planets (including the earth) revolve around the sun.

779

What does U.F.O stand for?

Unidentified Flying Object.

780

Which is the brightest star in the sky at night?

Sinus.

781

What method of healing is also known as shiatsu?

Acupressure.

782

What is Hypothermia?

It is a body condition in which the temperature falls suddenly as a result of exposure to extreme cold.

783

What is the thin flap of cartilage attached to the base of the tongue of terrestrial vertebrates called?

Epiglottis.

784

What is the term used to describe the remains of forests where the trees have been submerged or buried and the tree tissues have been replaced gradually by minerals such as silica or calcite?

Petrified Forest.

 

 


Last Updated on Wednesday, 30 April 2014 06:50