Ecosystem Practice Questions

NEET · Biology · 993 free MCQs with instant results and detailed explanations.

993
Total
206
Easy
439
Medium
348
Hard

Start Practicing Ecosystem

Take a timed quiz or customize your practice session

Quick Quiz (10 Qs) → Mock Test (25 Qs) ⚙ Customize

Topics in Ecosystem

Ecological Succession 171
Nutrient Cycling 167
Structure and Function 162
Ecological Pyramids 160
Food Chain and Food Web 168
Energy Flow 165

Sample Questions from Ecosystem

Here are 10 sample questions. Start a quiz to get randomized questions with scoring.

Q1
Easy
Which of the following components is a biotic factor in an ecosystem?
A. Soil
B. Water
C. Fungi
D. Sunlight
Show Answer & Explanation
Correct Answer: C
Fungi are living organisms, and hence they are categorized as biotic factors. In contrast, soil, water, and sunlight are abiotic factors.
Q2
Easy
In a food chain, which organism is typically considered a primary producer?
A. Herbivore
B. Carnivore
C. Plant
D. Decomposer
Show Answer & Explanation
Correct Answer: C
Plants are primary producers as they synthesize their own food through photosynthesis, forming the base of the food chain.
Q3
Easy
What is the role of decomposers in an ecosystem?
A. They produce energy
B. They consume primary producers
C. They break down dead organic matter
D. They compete with plants for sunlight
Show Answer & Explanation
Correct Answer: C
Decomposers break down dead organic matter, recycling nutrients back into the ecosystem, making them essential for nutrient cycling.
Q4
Medium
Which of the following best describes a food chain?
A. A linear sequence of organisms through which nutrients and energy pass
B. A complex network of feeding relationships among organisms
C. A diagrammatic representation of energy flow in an ecosystem
D. A diagram showing biodiversity across different habitats
Show Answer & Explanation
Correct Answer: A
A food chain represents a linear sequence of organisms where each level feeds on the previous one, showing the flow of energy and nutrients.
Q5
Medium
What is the primary role of decomposers in an ecosystem?
A. They convert solar energy into chemical energy.
B. They break down dead organic matter and recycle nutrients.
C. They compete with producers for resources.
D. They regulate population sizes of herbivores.
Show Answer & Explanation
Correct Answer: B
Decomposers play a crucial role by breaking down dead organic matter, thus recycling nutrients back into the ecosystem and maintaining soil health.
Q6
Medium
In an ecosystem, which trophic level has the least amount of energy available?
A. Producers
B. Primary consumers
C. Secondary consumers
D. Tertiary consumers
Show Answer & Explanation
Correct Answer: D
At the top of the food chain, tertiary consumers have the least energy available due to energy loss at each trophic level, typically around 90% loss.
Q7
Medium
Which of the following characteristics is NOT typical of a climax community?
A. High biodiversity
B. Stable species composition
C. Rapid changes in species
D. Well-established nutrient cycles
Show Answer & Explanation
Correct Answer: C
A climax community is characterized by stability, high biodiversity, and well-established nutrient cycles, so rapid changes in species are not typical.
Q8
Hard
In a particular ecosystem, if the primary productivity is 800 g/m²/year and the gross primary productivity is 1000 g/m²/year, what is the net primary productivity?
A. 100 g/m²/year
B. 200 g/m²/year
C. 300 g/m²/year
D. 400 g/m²/year
Show Answer & Explanation
Correct Answer: B
Net primary productivity (NPP) is calculated by subtracting the respiration rate from the gross primary productivity (GPP). Here, NPP = GPP - Respiration = 1000 g/m²/year - 800 g/m²/year = 200 g/m²/year.
Q9
Hard
Which of the following is an example of a keystone species in an ecosystem?
A. Decomposers like fungi
B. Predatory species like wolves
C. Dominant plant species
D. Invasive species
Show Answer & Explanation
Correct Answer: B
A keystone species, such as wolves in a forest ecosystem, has a disproportionately large effect on its environment relative to its abundance. They help maintain the population of other species, thereby supporting biodiversity.
Q10
Hard
In a food chain, if the producer has a biomass of 1000 kg, and the energy transferred to the primary consumer is 10%, what is the biomass of the primary consumer?
A. 100 kg
B. 50 kg
C. 10 kg
D. 200 kg
Show Answer & Explanation
Correct Answer: A
The biomass of the primary consumer can be determined as 10% of the producer's biomass. Thus, 10% of 1000 kg equals 100 kg.

Showing 10 of 993 questions. Start a quiz to practice all questions with scoring and timer.

Practice All 993 Questions →

Ecosystem — NEET Biology Practice Questions Online

This page contains 993 practice MCQs for the chapter Ecosystem in NEET Biology. The questions are organized by difficulty — 206 easy, 439 medium, 348 hard — so you can choose the right level for your preparation.

Every question includes a detailed explanation to help you understand the concept, not just memorize answers. Take a timed quiz to simulate exam conditions, or practice at your own pace with no time limit. This chapter covers 6 topics, giving you comprehensive coverage of the entire chapter.