Biosphere Questions and Answers

Biosphere MCQ (Multiple Choice Questions and Answers)

Question 1: Biosphere is defined as

(A) Part of the earth water and atmosphere which inhabits living organism

(B) Part of the soil where animals and plants are found

(C) Atmosphere in which life exists

(D) None of the above

Answer: (A)

Question 2: Biosphere consists of

(A) Lithosphere

(B) Atmosphere

(C) Hydrosphere

(D) All the above

Answer: (D)

Question 3: Component of biosphere related with soil is

(A) Lithosphere

(B) Hydrosphere

(C) Atmosphere

(D) None of the above

Answer: (A)

Question 4: Phenomenon of rain, dew, snow i.e., different forms of water coming to earth under force of gravity is called

(A) Geotropism

(B) Climatic factors

(C) Precipitation

(D) Calcification

Answer: (C)

Question 5: Process of evapo-transpiration and precipitation is called

(A) Carbon cycle

(B) Nitrogen cycle

(C) Hydrological cycle

(D) All the above

Answer: (C)

Question 6: Agents which make free atmospheric nitrogen available to plants are

(A) Lightening

(B) Free living nitrogen fixing bacteria

(C) Symbiotic nitrogen fixing bacteria

(D) All the above

Answer: (D)

Question 7: Maintenance of soil fertility without addition of nutrition is due to

(A) Floods

(B) Crop residue

(C) Favourable temperature

(D) Microbial activity

Answer: (D)

Question 8: A logical sequence of carbon cycle is

(A) Producer – Consumer – Decomposer

(B) Decomposer – Producer – Decomposer

(C) Consumer – Producer  – Consumer

(D) Producer – Decomposer – Consumer

Answer: (A)

Question 9: Rise of atmospheric temperature because of high concentration of carbon dioxide is known as

(A) Green house effect

(B) Biomagnification

(C) Pollution

(D) Ecotone

Answer: (A)

Question 10: Source of energy in the biosphere is 

(A) Producer

(B) Decomposer

(C) Sunlight

(D) Heat of earth

Answer: (C)

Question 11: Earth is an 

(A) Open system

(B) Closed system

(C) Both open and closed system

(D) Neither A nor B

Answer: (C)

Question 12: Biogeochemical cycles are also known as

(A) Sedimentary cycles

(B) Gaseous cycles

(C) Material cycling

(D) Cycles of water

Answer: (C)

Question 13: In one year one hectare of forest shall

(A) Consume 10 tonnes of CO2 and evolve 10 tonnes of O2

(B) Consume 20 tonnes of CO2 and evolve 10 tonnes of O2

(C) Consume 30 tonnes of CO2 and evolve 30 tonnes of O2

(D) Consume 30 tonnes of CO2 and evolve 10 tonnes of O2

Answer: (D)

Question 14: Amount of carbon fixed annually through photosynthesis is

(A) 4.6 x 1010 kg

(B) 7 x 1013 kg

(C) 7 x 1020 kg

(D) 4.6 x 1021 kg

Answer: (B)

Question 15: Climate of the world is threatened by

(A) Increasing concentration of atmospheric oxygen

(B) Decreasing amount of atmospheric oxygen

(C) Increasing amount of atmospheric carbon dioxide

(D) Decreasing amount of atmospheric carbon dioxide

Answer: (C)

Question 16: Green House gases are

(A) Absorbers of long-wave radiations from earth

(B) Transparent to both solar radiations and long-wave radiations from earth

(C) Absorbers of solar radiations for warming the atmosphere of earth

(D) Transparent to emissions from earth for passage into outer space

Answer: (A)

Question 17: Nonbiological nitrogen fixation is

(A) Electrochemical and photochemical

(B) Rhizobial

(C) Cyanobacterail

(D) None od the above

Answer: (A)

Question 18: Pseudomonas is an important component of nitrogen cycle. It

(A) Fixes elemental nitrogen

(B) Produces elemental nitrogen

(C) Transfers nitrogen

(D) Changes ammonium nitrogen to nitrate state

Answer: (B)

Question 19: Water cycle is made up of two overlapping cycles

(A) Ground water atmospheric cycles

(B) Surface water and atmospheric cycles

(C) Global and local cycles

(D) Oceanic and fresh water cycles

Answer: (C)

Question 20: Sedimentary cycle having a small gaseous component is found in

(A) Phosphorus

(B) Nitrogen

(C) Carbon

(D) Sulphur

Answer: (D)

Question 21: Earth is protected from ultra-violet radiations by means of 

(A) Ozone layer

(B) Nitrogen

(C) Oxygen

(D) Carbon dioxide

Answer: (A)

Question 22: Ozone layer occurs in

(A) Ionosphere

(B) Stratosphere

(C) Thermosphere

(D) Troposphere

Answer: (B)

Question 23: Ecosystems obtain nitrogen from outside through the process of

(A) Industrial fixation

(B) Electrochemical and photochemical fixation

(C) Biological fixation

(D) All the above

Answer: (D)

Question 24: Earth is an open system for

(A) Minerals

(B) Energy

(C) Gases

(D) Water

Answer: (B)

Question 25: Lithosphere is reservoir of

(A) Carbon

(B) Oxygen

(C) Phosphorous

(D) Nitrogen

Answer: (C) 

Question 26: Amount of nitrogen fixed by nitrogen fixing organisms is

(A) 70%

(B) 30%

(C) 50%

(D) 90%

Answer: (A)

Question 27: Carbon is found in lithosphere as

(A) Carbohydrate

(B) Carbonic acid

(C) Carbon

(D) Carbonate

Answer: (D)

Question 28: Which has a sedimentary cycle

(A) Nitrogen

(B) Carbon

(C) Water

(D) Sulphur

Answer: (D)

Question 29: Maximum control of hydrological cycle is exerted by

(A) Epiphytes

(B) Forests

(C) Plankton

(D) Grassland

Answer: (B)

Question 30: Ecological cycle directly driven by sunlight is

(A) Carbon

(B) Phosphorus

(C) Hydrologic

(D) Nitrogen

Answer: (C)

Question 31: Biosphere is

(A) Area occupied by living beings

(B) Plants of the world

(C) Plants of a particular area

(D) Special plants

Answer: (A)

Question 32: Source of carbon to plants is

(A) Carbon dioxide of carbonate rocks

(B) Fossil fuels

(C) Atmospheric carbon dioxide

(D) All the above

Answer: (C)

Question 33: Biogeochemical cycle refers to cycling of 

(A) Sediments

(B) Nutrient in the ecosystem

(C) Water

(D) Gases between plants and animals

Answer: (B)

Question 34: Gas being produced by paddy fields and involved in global warming is

(A) Chlorine

(B) Methane

(C)  CO2

(D) H2S

Answer: (B)

Question 35: Green house effect is warming due to

(A) Infra-red rays reaching earth

(B) Moisture layer in atmosphere

(C) Increase in temperature due to increase in carbon dioxide concentration of atmosphere

(D) Ozone layer of atmosphere

Answer: (C)

Question 36: Green house effect is related to

(A) Increased growth of green algae

(B) Global warming

(C) Cultivation of vegetables in houses

(D) Development of terrace gardens

Answer: (B)

Question 37: Green house gases include

(A) CO2, CFC, CH4 and NO2

(B) CO2, O2, N2, NO2 and NH3

(C) CH4, N2, CO2 and NH3

(D) CFC, CO2, NH3 and N2

Answer: (A)

Question 38: The circulation or cycling of elements in an ecosystem is known as

(A) Geological cycling

(B) Geo-chemical cycling

(C) Bio-geochemical cycling

(D) Chemical cycling

Answer: (C)

Question 39: The sphere of living matter found on the surface of earth comprises

(A) Lithosphere

(B) Hydrosphere

(C) Atmosphere

(D) Biosphere

Answer: (D)

Question 40: The term biosphere is used for a zone containing living beings

(A) In lithosphere, hydrosphere and atmosphere

(B) In lithosphere and hydrosphere

(C) In hydrosphere

(D) On lithosphere

Answer: (A)

Question 41: Biosphere is made of

(A) Living beings and their remains

(B) Living beings + Lithosphere + Hydrosphere + Atmosphere

(C) Living beings + Lithosphere

(D) Living organisms+ Lithosphere + Hydrosphere

Answer: (B)

Question 42: Which is not a green house gas

(A) Chlorofluorocarbon

(B) Methane

(C) Carbon dioxide

(D) Hydrogen

Answer: (D)

Question 43: Concentration of green house gases is increasing due to

(A) Deforestation

(B) Increased use of refrigerators

(C) Increased combustion of coal and petroleum

(D) All the above

Answer: (D)

Question 44: Which gas contributes more to green house effect


(B) Freon

(C) CO2

(D) CH4

Answer: (C)

Question 45: Which gas of the atmospheric holds up ultraviolet rays

(A) O2

(B) O3

(C) N2

(D) CO2

Answer: (B)

Question 46: Checking of re-radiating heat by atmospheric dust, O3, CO2, and water vapour is

(A) Ozone layer effect

(B) Solar effect

(C) Radioactive effect

(D) Green house effect

Answer: (D)

Question 47: Liberation of H2S/foul smell in water of tanks, ponds, etc. is due to

(A) Anaerobiosis

(B) Aerobiosis

(C) Psammophytes

(D) Biological magnification

Answer: (A)

Question 48: COand Obalance in atmosphere is due to

(A) Photosynthesis

(B) Respiration

(C) Leaf anatomy

(D) Photorespiration

Answer: (A)

Question 49: Biosphere is

(A) A protected area

(B) Ecosystem

(C) In which individuals interact

(D) Earth crust

Answer: (D)

Question 50: Fertiliser obtained from Sea Birds along the coast of Chile and Peru is

(A) Guano

(B) Bone meal

(C) Dung

(D) Urea

Answer: (A)