Q1. The process of nitrogen-fixation by bacteria does not take place in the presence of –
(a) molecular form of hydrogen
(b) elemental form of oxygen
(c) water
(d) elemental form of nitrogen
Q2. Rainfall patterns depend on –
(a) the underground water table
(b) the number of water bodies in an area
(c) the density pattern of human population in an area
(d) the prevailing season in an area
Q3. The nitrogen molecules present in an air can be converted into nitrates and nitrites by –
(a) a biological process of nitrogen fixing bacteria present in soil
(b) a biological process of carbon fixing factor present in soil
(c) any of the industries manufacturing nitrogenous compounds
(d) the plants used as cereal crops in field
Q4. Flow of energy in an ecosystem is always –
(a) unidirectional
(b) bidirectional
(c) multi directional
(d) no specific direction
Q5. The % of solar radiation absorbed by all the green plants for the process of photosynthesis is about –
(a) 1 %
(b) 5 %
(c) 9 %
(d) 10 %
Q6. Low visibility during cold weather is due to –
(a) formation of fossil fuel
(b) unburnt carbon particles or hydrocarbons suspended in air
(c) lack of adequate power supply
(d) none of these
Q7. Marked temperature changes in aquatic environment can affect –
(a) breeding of animals
(b) more growth of aquatic plants
(c) process of digestion in animals
(d) availability of nutrients
Q8. Which one of the following is not important for individual health?
(a) living in clean space
(b) good economic condition
(c) social equality and harmony
(d) living in a large and well-furnished house
Q9. The atmosphere of the earth is heated by radiations which are mainly –
(a) radiated by the sun
(b) re-radiated by land
(c) re-radiated by water
(d) re-radiated by land and water
Q10. In desert plants, rate of water loss gets reduced due to the presence of –
(a) stomata
(b) cuticle
(c) lignin
(d) suberin
Solutions
S1. Ans.(c)
S2. Ans.(b)
S3. Ans.(a)
S4. Ans.(a)
S5. Ans.(a)
S6. Ans.(b)
S7. Ans.(a)
S8. Ans.(d)
S9. Ans.(a)
S10. Ans.(b)
