Back to ECO SYSTEM
Your Progress
0 / 42 Answered
0
Correct
0
Incorrect
0%
Accuracy
NEET • BIOLOGY • ECO SYSTEM
Eco system practice · Hard
Try a question, then open “View answer” to check it. Sign in to submit answers and save progress.
Practice format and chapter quiz
The practice player uses single-correct-answer MCQs. Chapter quizzes help you review a topic; they are not full-length NEET mock papers.
Take a chapter quiz →
Showing 1-30 of 42 questions
1
Hard
1 of 42
Understanding
+4 | -1
Which one of the following statements is correct for secondary succession?
View answer and explanation
Correct option: A
It occurs on a deforested site
Option A (It occurs on a deforested site) is correct because secondary succession occurs in areas where previous life existed, such as a deforested site.
2
Hard
2 of 42
Understanding
+4 | -1
All successions irrespective of the habitat
proceed to which type of climax community?
proceed to which type of climax community?
View answer and explanation
Correct option: C
Mesic
Option C (Mesic) is correct because all successions tend to lead to a mesic climax community, which represents a balanced moisture condition.
3
Hard
3 of 42
Understanding
+4 | -1
Biomagnification will be maximum among which of the given trophic level in an aquatic ecosystem?
View answer and explanation
Correct option: D
Option D () is correct because biomagnification increases with each trophic level, so the highest trophic level will have the maximum concentration.
4
Hard
4 of 42
Application
+4 | -1
A pasture of 40 hectares has a biomass of 40 kg/hectare, or roughly calories of energy. Cattle grazing on this pasture are sold for beef. About how many calories of energy from the pasture reach human consumers of the beef?
View answer and explanation
Correct option: A
10000
Option A (10000) is correct because only about 1% of the energy from the pasture reaches human consumers due to energy loss at each trophic level.
5
Hard
5 of 42
Remembering
+4 | -1
The transfer of energy from one trophic level to another is governed by the 2nd law of thermodynamics. The average efficiency of energy transfer from herbivores to carnivores is
View answer and explanation
Correct option: B
0.1
Option B (0.1) is correct because, on average, only about 10% (or 0.1) of the energy is transferred from one trophic level to the next.
6
Hard
6 of 42
Understanding
+4 | -1
Assertion: Sedimentary nutrient cycles of phosphorus, calcium, magnesium etc. are considered as imperfect cycles.
Reason: These cycles caused by local disturbances get more easily disrupted as the bulk of material remains in the relatively inactive and immobile reservoir on the earth's crust.
Reason: These cycles caused by local disturbances get more easily disrupted as the bulk of material remains in the relatively inactive and immobile reservoir on the earth's crust.
View answer and explanation
Correct option: A
If both assertion and reason are true and reason is the correct explanation of assertion
Option A (If both assertion and reason are true and reason is the correct explanation of assertion) is correct because sedimentary nutrient cycles are imperfect due to the bulk of material remaining in immobile reservoirs.
7
Hard
7 of 42
Understanding
+4 | -1
The mosses which form dense extensive mats on the soil prevents:
View answer and explanation
Correct option: B
Soil erosion
Option B (Soil erosion) is correct because mosses, by forming dense mats, protect the soil surface from the impact of raindrops and wind, thus preventing erosion.
8
Hard
8 of 42
Understanding
+4 | -1
Edaphic nutrient cycles include
View answer and explanation
Correct option: D
All the above
Option D (All the above) is correct because edaphic nutrient cycles, which occur in the soil, can involve gaseous, partial sedimentary, and total sedimentary types.
9
Hard
9 of 42
Understanding
+4 | -1
Assertion: In a food chain, members of successive higher levels are fewer in number.
Reason: Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.
Reason: Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.
View answer and explanation
Correct option: A
If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
Option A (If both Assertion and Reason are correct and Reason is the correct explanation of Assertion) is correct because the number of organisms at higher trophic levels depends on the energy available from lower levels.
10
Hard
10 of 42
Understanding
+4 | -1
The changes that occur in successive seral stages to reach a climax community are
I. changes in the diversity of species of organisms
II. increase in the number of species and organisms
III. increase in the total biomass
Choose the correct option
I. changes in the diversity of species of organisms
II. increase in the number of species and organisms
III. increase in the total biomass
Choose the correct option
View answer and explanation
Correct option: D
I, II and III
Option D (I, II and III) is correct because all three statements describe changes that occur during ecological succession.
11
Hard
11 of 42
Understanding
+4 | -1
Assertion: Herbivores are also known as key industry animals because they convert plant matter into animal matter.
Reason: In an ecosystem decomposers play a vital role and they indirectly support the producers.
Reason: In an ecosystem decomposers play a vital role and they indirectly support the producers.
View answer and explanation
Correct option: B
If both assertion and reason are true but reason is not the correct explanation of assertion
Option B (If both assertion and reason are true but reason is not the correct explanation of assertion) is correct because both statements are true, but the reason doesn't explain why herbivores are called key industry animals.
12
Hard
12 of 42
Understanding
+4 | -1
Which of the following statements is not a major concern about our altering of the carbon cycle?
View answer and explanation
Correct option: B
High-sulphur fuels are used by power plants because they are less expensive than low-sulphur fuels
Option B (High-sulphur fuels are used by power plants because they are less expensive than low-sulphur fuels) is correct because while it is a pollution issue, it is not directly related to the carbon cycle.
13
Hard
13 of 42
Understanding
+4 | -1
Assertion (A): Many environmental scientists believe amphibians, including frogs, are good biological indicators of broader ecosystem health.
Reason (R): These organisms have intermediate positions in food chains, have permeable skins, and typically biphasic lives (aquatic larvae and terrestrial adults).
Reason (R): These organisms have intermediate positions in food chains, have permeable skins, and typically biphasic lives (aquatic larvae and terrestrial adults).
View answer and explanation
Correct option: A
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Option A (Both (A) & (R) are true and the (R) is the correct explanation of the (A)) is correct because amphibians' sensitivity to environmental changes makes them good indicators, and the reason explains why they are so sensitive.
14
Hard
14 of 42
Understanding
+4 | -1
Identify the correct statements:
A. Detrivores perform fragmentation.
B. The humus is further degraded by some microbes during mineralization.
C. Water soluble inorganic nutrients go down into the soil and get precipitated by a process called
leaching.
D. The detritus food chain begins with living organisms.
E. Earthworms break down detritus into smaller particles by a process called catabolism.
Choose the correct answer from the options given below:
A. Detrivores perform fragmentation.
B. The humus is further degraded by some microbes during mineralization.
C. Water soluble inorganic nutrients go down into the soil and get precipitated by a process called
leaching.
D. The detritus food chain begins with living organisms.
E. Earthworms break down detritus into smaller particles by a process called catabolism.
Choose the correct answer from the options given below:
View answer and explanation
Correct option: C
A, B, C only
Option C (A, B, C only) is correct because statements A, B, and C accurately describe processes in the ecosystem, while D and E are incorrect.
15
Hard
15 of 42
Understanding
+4 | -1
Assertion (A) : Petro plants yield Bio-diesel.
Reason (R) : Jatropa is rich in hydrocarbons.
Reason (R) : Jatropa is rich in hydrocarbons.
View answer and explanation
Correct option: B
Both A and R are correct and R is the correct explanation for A.
Option B (Both A and R are correct and R is the correct explanation for A) is correct because Jatropha, rich in hydrocarbons, is used to produce biodiesel, making both the assertion and reason true and related.
Explore Other Chapters in BIOLOGY
View All →
16
Hard
16 of 42
Remembering
+4 | -1
Pick the correct combination of gaseous
cycle and sedimentary cycle from the list
given below
cycle and sedimentary cycle from the list
given below
View answer and explanation
Correct option: A
Gaseous : C & N; Sedimentary : P & S
Option A (Gaseous : C & N; Sedimentary : P & S) is correct because carbon and nitrogen cycles are primarily gaseous, while phosphorus and sulphur cycles are primarily sedimentary.
17
Hard
17 of 42
Understanding
+4 | -1
Which of the following statements concerning acid precipitation is incorrect?
View answer and explanation
Correct option: A
Acids that enter the atmosphere primarily affect ecosystems located less than 100 kilometers from the source of the pollution
Option A is correct because acids can travel long distances in the atmosphere, affecting ecosystems far from the pollution source.
18
Hard
18 of 42
Remembering
+4 | -1
The two vegetations of an ecosystem are separated by:
View answer and explanation
Correct option: B
Ecoline
The correct answer is B (Ecoline) because an ecoline represents the boundary or transition zone between two different vegetation types or ecosystems.
19
Hard
19 of 42
Understanding
+4 | -1
Which of the following statement(s) is/are correct about biogeochemical cycle?
(i) Gaseous exchanges of phosphorus between organism and environment are negligible.
(ii) All biogeochemical cycles include both organisms and non-living components.
(iii) Most elements remain longest in the living portion of their cycle.
(iv) The chemical elements used by organisms in large quantities cycle back and forth between organisms and environment.
(i) Gaseous exchanges of phosphorus between organism and environment are negligible.
(ii) All biogeochemical cycles include both organisms and non-living components.
(iii) Most elements remain longest in the living portion of their cycle.
(iv) The chemical elements used by organisms in large quantities cycle back and forth between organisms and environment.
View answer and explanation
Correct option: B
(i), (ii) and (iv)
Option B ((i), (ii) and (iv)) is correct because gaseous exchanges of phosphorus are negligible, all biogeochemical cycles include organisms and non-living components, and elements used in large quantities cycle between organisms and the environment.
20
Hard
20 of 42
Understanding
+4 | -1
Consider the following statements.
(i) An ecosystem is a functional unit of nature and comprises abiotic and biotic components.
(ii) Abiotic components are organic materials.
(iii) Biotic components are producers, consumers and decomposers.
(iv) Energy flow is bidirectional.
Which two statements are correct?
(i) An ecosystem is a functional unit of nature and comprises abiotic and biotic components.
(ii) Abiotic components are organic materials.
(iii) Biotic components are producers, consumers and decomposers.
(iv) Energy flow is bidirectional.
Which two statements are correct?
View answer and explanation
Correct option: D
(i) and (iii)
Option D ((i) and (iii)) is correct because an ecosystem includes abiotic and biotic components, and biotic components consist of producers, consumers, and decomposers.
21
Hard
21 of 42
Understanding
+4 | -1
Size of organism finally reduces at higher trophic level in
View answer and explanation
Correct option: A
Auxiliary food chain
Option C (Predator food chain) is correct because in a predator food chain, the size of the organism generally increases at higher trophic levels, whereas in an auxiliary food chain, the size reduces.
22
Hard
22 of 42
Analyzing
+4 | -1
Which one option is incorrectly matched regarding biological magniècation of DDT in aquatic ecosystem.
View answer and explanation
Correct option: C
Fish-eating birds
Option D (Zooplankton - 0.003 ppm) is incorrectly matched because in an aquatic ecosystem, zooplankton should have a lower concentration of DDT compared to small fish due to biomagnification.
23
Hard
23 of 42
Understanding
+4 | -1
In ecosystem at which trophic level human are placed :
a. may be second trophic level
b. may be third trophic level
c. may be first trophic level
d. may be fourth trophic level
a. may be second trophic level
b. may be third trophic level
c. may be first trophic level
d. may be fourth trophic level
View answer and explanation
Correct option: B
a, b, d
Option B (a, b, d) is correct because humans can occupy the second, third, or fourth trophic levels depending on their diet.
24
Hard
24 of 42
Understanding
+4 | -1
Assertion: Secondary succession always involves a predictable species sequence and ends up with the same climax community as existed prior to the disturbance.
Reason: A pond never be considered as a self-sustained ecosystem as it lacks all the structural and functional components that work as a unit in an ecosystem.
Reason: A pond never be considered as a self-sustained ecosystem as it lacks all the structural and functional components that work as a unit in an ecosystem.
View answer and explanation
Correct option: D
If both assertion and reason are false
Option D (If both assertion and reason are false) is correct because secondary succession doesn't always follow the same sequence, and a pond can be a self-sustained ecosystem.
25
Hard
25 of 42
Understanding
+4 | -1
After the primary producer level in an ecosystem;
View answer and explanation
Correct option: B
No new chemical energy is added at successive trophic levels.
Option B (No new chemical energy is added at successive trophic levels) is correct because only the primary producers can create new chemical energy from sunlight.
26
Hard
26 of 42
Remembering
+4 | -1
A complex of several species and communities in various stages of succession maintained under similar climatic conditions is known as:
View answer and explanation
Correct option: A
Biome
Option A (Biome) is correct because a biome is a large community of plants and animals that occupies a distinct region and is maintained under similar climatic conditions.
27
Hard
27 of 42
Remembering
+4 | -1
In the vast marine ecosystem, certain sea develop red colouration. This red colour is due to the presence of large population of which one of the following organisms?
View answer and explanation
Correct option: A
Trichodesmium erythraeum
The correct answer is A (Trichodesmium erythraeum) because this cyanobacterium is known to cause red tides due to its red pigment.
28
Hard
28 of 42
Understanding
+4 | -1
Assertion: The pyramid of biomass indicates the decrease in biomass at each trophic level from base to apex.
Reason: Parasites have inverted pyramid for biomass.
Reason: Parasites have inverted pyramid for biomass.
View answer and explanation
Correct option: B
If both assertion and reason are true but reason is not the correct explanation of assertion
Option B (If both assertion and reason are true but reason is not the correct explanation of assertion) is correct because both statements are true, but the reason doesn't explain why the pyramid of biomass generally decreases.
29
Hard
29 of 42
Understanding
+4 | -1
Given below are two statements
Statement I: Any calculation of energy content, biomass or numbers has to be include all organism at that trophic level.
Statement II: One must remember that the trophic level represents a functional level, not a species as such
Choose the correct answer from the option given below:
Statement I: Any calculation of energy content, biomass or numbers has to be include all organism at that trophic level.
Statement II: One must remember that the trophic level represents a functional level, not a species as such
Choose the correct answer from the option given below:
View answer and explanation
Correct option: D
Both Statement I and Statement II are correct
Option D (Both Statement I and Statement II are correct) is correct because both statements accurately describe how trophic levels are analyzed and represented in ecosystems.
30
Hard
30 of 42
Understanding
+4 | -1
Productivity is the rate of production of biomass expressed in terms of
View answer and explanation
Correct option: C
(ii) and (iv)
Option C ((ii) and (iv)) is correct because productivity is measured as biomass production per unit area per unit time, expressed as g m⁻² yr⁻¹ or kcal m⁻² yr⁻¹.
Revision notes and key takeaways
Review ECO SYSTEM in your textbook or class notes, then use this set to check your understanding.
Key Takeaways
- ✓ This set contains 42 single-correct-answer MCQs on ECO SYSTEM.
- ✓ Try each question before opening its answer. Read the explanation where one is available.
- ✓ Sign in to save submitted answers. Revisit incorrect answers alongside your textbook or class notes.
Showing 1-30 of 42 questions
Continue Your Practice
📚 Switch Set (HARD)
0
/42
0✓
0✗
0% Accuracy