General Knowledge Question and Answer in Science

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.

No.	Question	Answer
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.