Ecosystem — NEET UG practice

87 questions

Practice NEET UG Ecosystem questions free — each with a detailed solution, graded instantly. Nothing is saved; log in to track your accuracy and build a streak.

Start free practice

Sample questions with solutions

Q1 · 2026

Match List I with List II:

List-I		List-II
A.	Productivity	I.	Gross primary productivity minus respiration losses
B.	Net primary productivity	II.	Rate of formation of new organic matter by consumers
C.	Gross primary productivity	III.	Rate of biomass production
D.	Secondary productivity	IV.	Rate of production of organic matter during photosynthesis

Choose the correct answer from the options given below:

A.
A-III, B-I, C-IV, D-II
B.
A-I, B-II, C-III, D-IV
C.
A-I, B-III, C-IV, D-II
D.
A-III, B-I, C-II, D-IV

Answer: A

Define Productivity: it simply refers to the rate of biomass production in an ecosystem. So A matches with III.
Define Gross Primary Productivity (GPP): this is the rate at which producers make organic matter through photosynthesis. So C matches with IV.
Define Net Primary Productivity (NPP): since producers also use up some of this energy in their own respiration, the leftover amount is the NPP.

NPP = GPP - R

So B matches with I.

Define Secondary Productivity: this is the rate at which consumers (not producers) form new organic matter by consuming other organisms. So D matches with II.

Hence, the correct matching is A-III, B-I, C-IV, D-II, so the answer is A.

Q2 · 2026

Match List I with List II:

List-I (Phase of cell cycle)		List-II (Activity)
A.	Decomposition	I.	Accumulation of dark coloured amorphous colloidal substance
B.	Detritus	II.	Release of inorganic nutrients by the activity of microbes in soil
C.	Mineralisation	III.	Breaking down of complex organic matter into inorganic substances
D.	Humification	IV.	Dead remains of plants and animals including fecal matter

Choose the correct answer from the options given below:

A.
A-IV, B-III, C-I, D-II
B.
A-III, B-IV, C-II, D-I
C.
A-I, B-II, C-III, D-IV
D.
A-III, B-II, C-I, D-IV

Answer: B

Define Decomposition: it is the process of breaking down complex organic matter into simpler inorganic substances. So A matches with III.
Define Detritus: this refers to the dead remains of plants and animals, including fecal matter, which acts as the raw material for decomposition. So B matches with IV.
Define Mineralisation: during decomposition, microbes break down humus further and release inorganic nutrients back into the soil. So C matches with II.
Define Humification: this is the process where a dark coloured, amorphous, colloidal substance (humus) accumulates in the soil. So D matches with I.

Hence, the correct matching is A-III, B-IV, C-II, D-I, so the answer is B.

Q3 · 2026

Ecological pyramids represent the relationship between the organisms at different trophic levels and they are generally inverted for:

A.
Pyramid of number in grassland
B.
Pyramid of energy in pond ecosystem
C.
Pyramid of biomass in grassland
D.
Pyramid of biomass in sea

Answer: D

Recall the pyramid of energy: since energy is always lost as heat while moving to the next trophic level, the pyramid of energy is always upright, whatever the ecosystem — so option B is ruled out.
Check pyramid of number and biomass in grassland: here, a large number of small producers (grasses) support fewer herbivores and even fewer carnivores, and the same pattern holds for biomass. So both are upright, ruling out options A and C.
Check pyramid of biomass in the sea: in oceans, the producers are tiny phytoplankton with a very short lifespan and small standing biomass at any given instant, even though they reproduce and get consumed rapidly. Meanwhile, the consumers (zooplankton, fish) have a much larger standing biomass. This makes the pyramid of biomass in the sea inverted.

Hence, the answer is D. Pyramid of biomass in sea.

Do more with a free account

Take it as a timed mock test
Build a daily streak
Track accuracy & progress
Save questions to your library