MCQs on Ecology

Ecology is the branch of science that deals with the relationship of organisms with each other and with the surroundings. Ecology is studied at the organism, population, community, ecosystem and biosphere levels. It refers to any form of biodiversity. The study of ecology is closely related to the field of genetics, physiology, evolution and behaviour.

Given below are important MCQs on Ecology to analyse your understanding of the topic. The answers are also given for your reference.

Ecology MCQs

1. The natural place of an organism or community is known as

1. Niche
2. Biome
3. Habitat
4. Habit

The correct answer is – 3. Habitat.

2. Which is the renewable exhaustible natural energy resource?

1. Coal
2. Petroleum
3. Kerosene
4. Biomass

The correct answer is – 4. Biomass.

Also read: Coal and Petroleum

3. According to Shelford’s Law of Tolerance, the organisms wide environmental factor tolerance limit show

1. Narrow distribution with low population size
2. Wide distribution with high population size
3. Narrow distribution with high population size
4. Wide distribution with low population size

The correct answer is – 2. Wide distribution with high population size.

4. Plants growing under direct sunlight are known as

1. Heliophytes
2. Sciophytes
3. Psamophytes
4. Dicots

The correct answer is – 1. Heliophytes.

5. Plants growing under shade are known as

1. Psamophytes
2. Sciophytes
3. Heliophytes
4. Monocots

The correct answer is – 2. Sciophytes.

6. An orchid living on a tree exhibits

1. Predator
2. Mutualism
3. Commensalism
4. Parasitism

The correct answer is – 3. Commensalism.

Also read: Parasitism

7. Which statement is correct with respect to the food chain?

1. Every component of the food chain forms a trophic level
2. Inter-relation between different food chains is known as a food web
3. All the chains formed by nutritional relations is used to understand energy flow.
4. All of the above

The correct answer is – 4. All of the above.

8. The process of vernalization is practised in

1. Cold countries
2. Hot countries
3. Only in sub-tropical countries
4. Only in tropical countries

The correct answer is – 1. Cold countries.

Also read: Photoperiodism and Vernalization

9. Which of the following requires maximum energy?

1. Secondary consumer
2. Decomposer
3. Primary consumer
4. Primary producer

The correct answer is – 4. Primary producer.

10. The bottom area where production is less than respiration in a pond ecosystem is termed as

1. Profundal zone
2. Tidal zone
3. Benthic zone
4. Limnetic zone

The correct answer is – 1. Profundal zone.

Also read: Aquatic Ecosystem

11. Which is not the characteristic of ‘r’ selected species?

1. Reproduce quickly
2. Parental care
3. A low survival rate of progenies
4. Produce a large number of progenies

The correct answer is – 2. Parental care.

12. Which is not the characteristic of a population?

1. Natality
2. Mortality
3. Stratification
4. Sex ratio

The correct answer is – 3. Stratification.

Also read: Introduction to Population Growth

13. Lincoln index measures

1. Population mortality rate
2. Population natality rate
3. Population size
4. Population density

The correct answer is – 3. Population size.

14. Allelopathy refers to

1. Inhibition of growth of one species by another by the production of toxins
2. Inhibition of sporulation of pathogen by the host
3. Altering the reproductive cycle of one organism by another
4. Inhibition of growth of one species by another by preventing reproduction

The correct answer is – 1. 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

1. Ecological capacity
2. Ecological efficiency
3. Ecological assimilation
4. Ecological potential

The correct answer is – 2. Ecological efficiency.

Also read: Energy Flow in an Ecosystem

16. The ability of a population to increase under ideal environmental conditions is called

1. Natality
2. Carrying capacity
3. Biotic potential
4. Absolute natality

The correct answer is – 3. Biotic potential.

17. In an ecosystem, the energy flow is always

1. Always unidirectional
2. Always bidirectional
3. In any direction
4. Always down directional

The correct answer is – 1. Always unidirectional.

Also read: Ecosystem

18. In thermal stratification, the middle region which shows vertical temperature change is called

1. Mesolimnion
2. Epilimnion
3. Metalimnion
4. Hypolimnion

The correct answer is – 3. Metalimnion.

19. Select a non-denitrifying bacteria

1. Pseudomonas aeruginosa
2. Thiobacillus
3. Thiobacillus denitrificans
4. Bacillus ramosus

The correct answer is – 4. Bacillus ramosus.

20. Which one is a ‘K’ selected species?

1. Aspergillus
2. Human
3. Taraxacum
4. Grass

The correct answer is – 2. Human.

21. All species of Lemur are endemic to which area?

1. Madagascar
2. Seychelles Island
3. Galapagos Island
4. New Caledonia

The correct answer is – 1. Madagascar.

22. The upper part of an aquatic ecosystem contains

1. Nekton
2. Plankton
3. Benthos
4. both (1) and (2)

The correct answer is – 2. Plankton.

23. What type of food chain is it?

dead animals → blowfly maggot →  maggots → frog → snake

1. Detrital food chain
2. Decomposer food chain
3. Predator food chain
4. Grazing food chain

The correct answer is – 1. Detrital food chain.

24. Identify the mismatched pair

1. Tundra – Permafrost
2. Savanna – Acacia trees
3. Prairie – Epiphytes
4. Coniferous forest – Evergreen trees

The correct answer is – 3. Prairie – Epiphytes.

25. “The pyramid of energy is always upright” states that

1. The energy conversion efficiency of herbivores is better than carnivores
2. The energy conversion efficiency of carnivores is better than herbivores
3. Producers have the lowest energy conversion efficiency
4. Energy conversion efficiency is the same in all trophic levels

The correct answer is – 1. 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?

1. The birds stopped laying eggs
2. The eggs laid by the birds did not hatch
3. The snakes ate the eggs
4. The DDT spray killed all the birds

The correct answer is – 2. The eggs laid by the birds did not hatch.

27. Which of the following lake zones has phytoplanktons in abundance?

1. Littoral zone
2. Benthic zone
3. Limnetic zone
4. Profundal zone

The correct answer is – 3. Limnetic zone.

28. Plant species with a wide range of genetic distribution evolve into a local population known as

1. Ecotype
2. Population
3. Ecosystem
4. Biome

The correct answer is – 1. Ecotype.

29. dB is the abbreviation used for the quantitative expression of

1. The density of bacteria in a medium
2. A Particular Pollutant
3. Dominant Bacillus in a culture
4. A pesticide

The correct answer is – 2. A Particular Pollutant.

30. The eggshell of birds becomes thin by the pollution from pesticides due to the interference in the activity of

1. Calmodulin
2. MgATPase
3. CaATPase
4. Calcium

The correct answer is – 3. CaATPase.

For more information on Biology topics or to find other MCQs, explore BYJU’S website.

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