MCQ Questions on Ecology
1. The natural place of an organism or community is known as
(a) Niche
(b) Biome
(c) Habitat
(d) Habit
Answer
Answer: (c) Habitat
2. Which is the renewable exhaustible natural energy resource?
(a) Coal
(b) Petroleum
(c) Kerosene
(d) Biomass
Answer
Answer: (d) Biomass
3. According to Shelford’s Law of Tolerance, the organisms wide environmental factor tolerance limit show
(a) Narrow distribution with low population size
(b) Wide distribution with high population size
(c) Narrow distribution with high population size
(d) Wide distribution with low population size
Answer
Answer: (b) Wide distribution with high population size
4. Plants growing under direct sunlight are known as
(a) Heliophytes
(b) Sciophytes
(c) Psamophytes
(d) Dicots
Answer
Answer: (a) Heliophytes
5. Plants growing under shade are known as
(a) Psamophytes
(b) Sciophytes
(c) Heliophytes
(d) Monocots
Answer
Answer: (b) Sciophytes
6. An orchid living on a tree exhibit
(a) Predator
(b) Mutualism
(c) Commensalism
(d) Parasitic
Answer
Answer: (c) Commensalism
7. Which statement is correct with respect to the food chain?
(a) Every component of food chain forms trophic level
(b) Inter-relation between different food chains is known as a food web
(c) All the chains formed by nutritional relations is used to understand energy flow.
(d) All of the above
Answer
Answer: (d) All of the above
8. The process of vernalization is practised in
(a) Cold countries
(b) Hot countries
(c) Only in sub-tropical countries
(d) Only in tropical countries
Answer
Answer: (a) Cold countries
9. Which of the following requires maximum energy?
(a) Secondary consumer
(b) Decomposer
(c) Primary consumer
(d) Primary producer
Answer
Answer: (d) Primary producer
10. The bottom area where production is less than respiration in a pond ecosystem is termed as
(a) Profundal zone
(b) Tidal zone
(c) Benthic zone
(d) Limnetic zone
Answer
Answer: (a) Profundal zone
11. Which is not the characteristic of ‘r’ selected species?
(a) Reproduce quickly
(b) Parental care
(c) A low survival rate of progenies
(d) Produce a large number of progenies
Answer
Answer: (b) Parental care
12. Which is not the characteristic of a population?
(a) Natality
(b) Mortality
(c) Stratification
(d) Sex ratio
Answer
Answer: (c) Stratification
13. Lincoln index measures
(a) Population mortality rate
(b) Population natality rate
(c) Population size
(d) Population density
Answer
Answer: (c) Population size
14. Allelopathy refers to
(a) Inhibition of growth of one species by another by the production of toxins
(b) Inhibition of sporulation of pathogen by the host
(c) Altering the reproductive cycle of one organism by another
(d) Inhibition of growth of one species by another by preventing reproduction
Answer
Answer: (a) Inhibition of growth of one species by another by the production of toxins
15. The ratio between energy flow at different points in a food chain is known as
(a) Ecological capacity
(b) Ecological efficiency
(c) Ecological assimilation
(d) Ecological potential
Answer
Answer: (b) Ecological efficiency
16. The ability of a population to increase under ideal environmental conditions is called
(a) Natality
(b) Carrying capacity
(c) Biotic potential
(d) Absolute natality
Answer
Answer: (c) Biotic potential
17. In an ecosystem, the energy flow is always
(a) Always unidirectional
(b) Always bidirectional
(c) In any direction
(d) Always down directional
Answer
Answer: (a) Always unidirectional
18. In thermal stratification, the middle region which shows vertical temperature change is called
(a) Mesolimnion
(b) Epilimnion
(c) Metalimnion
(d) Hypolimnion
Answer
Answer: (c) Metalimnion
19. Select a non-denitrifying bacteria
(a) Pseudomonas aeruginosa
(b) Thiobacillus
(c) Thiobacillus denitrificans
(d) Bacillus ramosus
Answer
Answer: (d) Bacillus ramosus
20. Which one is a ‘K’ selected species?
(a) Aspergillus
(b) Human
(c) Taraxacum
(d) Grass
Answer
Answer: (b) Human
21. All species of Lemur are endemic to which area?
(a) Madagascar
(b) Seychelles Island
(c) Galapagos Island
(d) New Caledonia
Answer
Answer: (a) Madagascar
22. The upper part of an aquatic ecosystem contains
(a) Nekton
(b) Plankton
(c) Benthos
(d) both (1) and (2)
Answer
Answer: (b) Plankton
23. What type of food chain is it?
dead animals → blowfly maggot → maggots → frog → snake
(a) Detrital food chain
(b) Decomposer food chain
(c) Predator food chain
(d) Grazing food chain
Answer
Answer: (a) Detrital food chain
24. Identify the mismatched pair
(a) Tundra – Permafrost
(b) Savanna – Acacia trees
(c) Prairie – Epiphytes
(d) Coniferous forest – Evergreen trees
Answer
Answer: (c) Prairie – Epiphytes
25. “The pyramid of energy is always upright” states that
(a) The energy conversion efficiency of herbivores is better than carnivores
(b) The energy conversion efficiency of carnivores is better than herbivores
(c) Producers have the lowest energy conversion efficiency
(d) Energy conversion efficiency is the same in all trophic levels.
Answer
Answer: (a) The energy conversion efficiency of herbivores is better than carnivores
26. The population of birds declined in an area where DDT was extensively used. Why?
(a) The birds stopped laying eggs
(b) The eggs laid by the birds did not hatch
(c) The snakes ate the eggs
(d) The DDT spray killed all the birds
Answer
Answer: (b) The eggs laid by the birds did not hatch
27. Which of the following lake zones has phytoplanktons in abundance?
(a) Littoral zone
(b) Benthic zone
(c) Limnetic zone
(d) Profundal zone
Answer
Answer: (c) Limnetic zone
28. Plant species with a wide range of genetic distribution evolve into a local population known as
(a) Ecotype
(b) Population
(c) Ecosystem
(d) Biome
Answer
Answer: (a) Ecotype
29. dB is the abbreviation used for the quantitative expression of
(a) Density of bacteria in a medium
(b) A Particular Pollutant
(c) Dominant Bacillus in a culture
(d) A pesticide
Answer
Answer: (b) A Particular Pollutant
30. The eggshell of birds becomes thin by the pollution from pesticides due to the interference in the activity of
(a) Calmodulin
(b) MgATPase
(c) CaATPase
(d) Calcium
Answer
Answer: (c) CaATPase