We have compiled the NCERT MCQ Questions for Class 12 Biology Chapter 14 Ecosystem with Answers Pdf free download covering the entire syllabus. Practice MCQ Questions for Class 12 Biology with Answers on a daily basis and score well in exams. Refer to the Ecosystem Class 12 MCQs Questions with Answers here along with a detailed explanation.
Ecosystem Class 12 MCQs Questions with Answers
Multiple Choice Type Questions
Question 1.
Given below is one of the types of ecological pyramids. This type represents
(a) Pyramid of numbers in a grassland
(b) Pyramid of biomass in a follow land
(c) Pyramid of biomass in a lake
(d) Energy pyramid in a spring
Answer
Answer: (c) Pyramid of biomass in a lake
Question 2.
Energy transferred from one trophic level to another
(a) 5%
(b) 10%
(c) 15%
(d) 20%
Answer
Answer: (b) 10%
Question 3.
Maximum absorption of rainfall water is done by
(a) Tropical deciduous forest
(b) Tropical evergreen forest
(c) Tropical savannah
(d) Scrule forest
Answer
Answer: (b) Tropical evergreen forest
Question 4.
Which of the following is called as a detrivore?
(a) An animal feeding on decaying organic matter
(b) An animal feeding on a plant
(c) A plant feeding on an animal
(d) An animal feeding on another animal
Answer
Answer: (a) An animal feeding on decaying organic matter
Question 5.
The pyramid of energy is always upright for any ecosystem. This situation indicates the fact that:
(a) producers have the lowest energy conversion efficiency
(b) carnivores have a better energy conversion efficiency
(c) energy, conversion efficiency is the same in all trophic levels
(d) herbivores have a better energy conversion efficiency than carnivores.
Answer
Answer: (d) herbivores have a better energy conversion efficiency than carnivores.
Question 6.
Which of the following pairs is mismatched?
(a) Tundra-permafrost
(b) Savanna-Acacia trees
(c) Praire-epiphytes
(d) Coniferous forest-evergreen trees
Answer
Answer: (c) Praire-epiphytes
Question 7.
The most abundant element present in the plants is
(a) nitrogen
(b) manganese
(c) iron
(d) carbon
Answer
Answer: (d) carbon
Question 8.
These belong to the category of primary consumers
(a) Insects and cattle
(b) Eagle and snakes
(c) Water insects
(d) Snakes and frogs
Answer
Answer: (a) Insects and cattle
Question 9.
Which of the following is expected to have the highest value (gm/m²/yr) in a grassland ecosystem?
(a) Tertiary production
(b) Gross production
(c) Net production
(d) Secondary production
Answer
Answer: (b) Gross production
Question 10.
Largest reservoir of sulphur is
(a) Atmosphere
(b) Rocks
(c) Ocean
(d) Lake
Answer
Answer: (b) Rocks
Question 11.
Maximum productivity is found in
(a) Grassland
(b) Desert
(c) Ocean
(d) Tropical rain forest
Answer
Answer: (c) Ocean
Question 12.
Concentration of nitrogen remains constant by
(b) Nitrogen cycle
(b) Thundering and lightning
(c) Enzymes
(d) Both (a) and (b)
Answer
Answer: (d) Both (a) and (b)
Question 13.
In the phosphorus cycle, phosphate becomes available by weathering of rocks first to
(a) Consumers
(b) Producers
(c) Decomposers
(d) None of these
Answer
Answer: (b) Producers
Question 14.
If there was no CO2 in the earth’s atmosphere, the temperature of the earth’s surface would be
(a) Same as the present
(b) Less than the present
(c) Higher than the present
(d) Depends on the amount of O2 in the atmosphere
Answer
Answer: (b) Less than the present
Question 15.
Bacterial role in carbon cycle is
(a) Chemosynthesis
(b) Photosynthesis
(c) Breakdown of organic matter
(d) Assimilation of nitrogen compounds
Answer
Answer: (c) Breakdown of organic matter
Question 16.
Which important greenhouse gas, other than methane is being produced from the agricultural fields?
(a) Arsine
(b) Sulphur dioxide
(c) Ammonia
(d) Nitrous oxide
Answer
Answer: (d) Nitrous oxide
Question 17.
Zone of atmosphere near the ground is
(a) Troposphere
(b) Stratosphere
(c) Homosphere
(d) All of these
Answer
Answer: (a) Troposphere
Question 18.
CO2 content of atmosphere is about
(a) 6.5%
(b) 3.334%
(c) 0.34%
(d) 0.034%
Answer
Answer: (d) 0.034%
Question 19.
Ultraviolet radiation from sunlight causes a reaction which produces
(a) O3
(b) SO2
(c) CO
(d) CH4
Answer
Answer: (a) O3
Question 20.
Mr. X is eating curd/yoghurt. For this food intake in a food chain he should be considerd as Occupying
(a) First trophic level
(b) Second trophic level
(c) Third trophic level
(d) Fourth trophic level
Answer
Answer: (b) Second trophic level
Fill in the Blanks
Question 1.
Inverted pyramid is generally found in ………………….
Answer
Answer: deep water bodies
Question 2.
Humus serves as a reservoir of ………………….
Answer
Answer: nutrients
Question 3.
In oceans, the productivity is generally limited by ………………….
Answer
Answer: nitrogen
Question 4.
Certain …………………. changes sulphides to sulphates.
Answer
Answer: bacteria
Question 5.
Composition of the atmosphere is quite uniform upto a height of …………………. kilometres.
Answer
Answer: 80
Question 6.
Vertical distribution of different species occupying different levels’is called ………………….
Answer
Answer: stratification
Question 7.
…………………. is the rate of formation of new organic matter by consumers.
Answer
Answer: secondary productivity
Question 8.
Dead plant parts and animal remains are called ………………….
Answer
Answer: detritus
Question 9.
Nutrient cycles are also known as ………………….
Answer
Answer: biogeochemical cycles
Question 10.
Layer of ozone occurs at a height of about to …………………. km in the atmosphere.
Answer
Answer: 25-50.
Write True or False
Question 1.
Lions and wolves occupy the same trophic level.
Answer
Answer: True
Question 2.
Savannahs are tropical rain forests.
Answer
Answer: False
Question 3.
Pyramids of numbers deals with the number of individuals in a community.
Answer
Answer: False
Question 4.
Hygrometer is used to measure the relative humidity.
Answer
Answer: True
Question 5.
Tropical forest occur in India in Rajasthan.
Answer
Answer: True
Question 6.
Pyramid of numbers in a pond ecosystem is inverted.
Answer
Answer: False
Question 7.
The maximum biomass occurs in temperate forests.
Answer
Answer: False
Question 8.
Man-made ecosystems have many dominant plant species.
Answer
Answer: False
Question 9.
Mineral cycles are not balanced.
Answer
Answer: True
Question 10.
Earth is an open system regarding matter.
Answer
Answer: False
One Word Questions
Question 1.
Give an alternate term for ecological pyramids.
Answer
Answer: Eltonian pyramids.
Question 2.
Name any vesperal animal.
Answer
Answer: Rabbit.
Question 3.
How deep in sea, producers are present?
Answer
Answer: Upto 200 m.
Question 4.
Name any one Eutrophic lake.
Answer
Answer: Dal lake in Kashmir.
Question 5.
Name any denitrifying bacteria.
Answer
Answer: Pseudomonas aeruginosa.
Question 6.
For how long the entire CO2 of the air can last with its use in photosynthesis by green plants?
Answer
Answer: 1 year.
Question 7.
Name the dark coloured amorphorus substance accumulated as a result of humification.
Answer
Answer: Humus.
Question 8.
What is unit of energy measurement for energy pyramids?
Answer
Answer: Kcalm-2yr-1
Question 9.
Which is the most stable ecosystem?
Answer
Answer: Oceans.
Question 10.
In a food chain, the maximum population is of which organisms?
Answer
Answer: Producers.
Match the Following
Column I | Column II |
1. Primary productivity | A. Bacteria, Fungi |
2. Natural ecosystem | B. Consumers |
3. Desert | C. Lake, Forest |
4. Decomposers | D. Biome |
5. Secondary productivity | E. Producers |
Answer
Answer:
Column I | Column II |
1. Primary productivity | E. Producers |
2. Natural ecosystem | C. Lake, Forest |
3. Desert | D. Biome |
4. Decomposers | A. Bacteria, Fungi |
5. Secondary productivity | B. Consumers |
Hope the information shed above regarding NCERT MCQ Questions for Class 12 Biology Chapter 14 Ecosystem with Answers Pdf free download has been useful to an extent. If you have any other queries of CBSE Class 12 Biology Ecosystem MCQs Multiple Choice Questions with Answers, feel free to reach us so that we can revert back to us at the earliest possible.