Free Ecosystems MCQs with Answers
69 Ecosystems MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
An ecosystem consists of organisms interacting with one another and with abiotic factors such as light, water, soil and temperature. The topic covers populations and communities, food chains and webs, trophic levels, ecological pyramids, energy flow, nutrient cycles and ecological succession.
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- A. Microbiology
- B. Biotechnology
- C. Marine biology
- D. Freshwater biology
Explanation: The correct answer is Freshwater biology because this field specifically focuses on the ecological dynamics and sustainability of…
Correct answer: Freshwater biology- A. Hydra
- B. Sponges
- C. Coral reefs
- D. Colonies of jellyfish
Explanation: The correct answer is Coral reefs. Coral reefs are known as the 'rain forests of the ocean' because they support a vast array of marine…
Correct answer: Coral reefs- A. I
- B. II
- C. III
- D. IV
Explanation: The energy transfer between trophic levels in a food chain is inefficient, with only about 10% of energy being transferred to the next…
Correct answer: I- A. 10 J
- B. 100 J
- C. 1,000 J
- D. 10,000 J
Explanation: In an energy pyramid, energy decreases as it moves up trophic levels due to the 10% rule, which states that only about 10% of the energy…
Correct answer: 100 J- A. Tundra
- B. Grassland
- C. Tropical rain forest
- D. Temperate deciduous forests
Explanation: The correct answer is the tundra. The tundra biome is known for its extremely cold climate, with average temperatures remaining low…
Correct answer: Tundra- A. Low altitude
- B. Heavy rainfall
- C. Highly fertile soil
- D. Short summer season
Explanation: The correct answer is that coniferous forests mainly comprise evergreen coniferous trees due to the short summer season.
Correct answer: Short summer season- A. Low precipitation, High evaporation
- B. Low precipitation, Low evaporation
- C. High precipitation, Low evaporation
- D. High precipitation, High evaporation
Explanation: Grassland ecosystems often experience low precipitation and high evaporation, which together contribute to limited soil moisture.
Correct answer: Low precipitation, High evaporation- A. Fish in a river
- B. Minerals in soil
- C. Mosquito larva in a pond
- D. Orchids in tropical rainforest
Explanation: Abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of…
Correct answer: Minerals in soil- A. I only
- B. II only
- C. I and III
- D. II and III
Explanation: The first stage of primary succession involves the establishment of a pioneer community, which is typically composed of species such as…
Correct answer: I and III- A. In well-aerated soils
- B. In water-logged soil
- C. In root nodules of leguminous plants
- D. On the root surfaces of leguminous plants
Explanation: Denitrifying bacteria thrive in environments where oxygen is limited, such as water-logged soils.
Correct answer: In water-logged soil11. In evergreen coniferous trees, presence of small, waxy and needles-like leaves is significant to:
- A. Allow snow to build up on their branches
- B. Produce more wind resistance in cold season
- C. Capture maximum sunlight for photosynthesis
- D. Reduce water loss by evaporation during cold season
Explanation: The waxy coating and needle-like shape help reduce water loss by evaporation during cold season.So option D is correct.Other…
Correct answer: Reduce water loss by evaporation during cold season- A. Acidic soil and low rainfall
- B. High temperature and acidic soil
- C. High rainfall and low temperature
- D. Low rainfall and grazing by animals
Explanation: Grassland biomes are maintained by several factors including low rainfall, which limits tree growth and encourages grasses to thrive.
Correct answer: Low rainfall and grazing by animals- A. tundra
- B. grassland.
- C. temperate rain forest.
- D. temperate deciduous forest
Explanation: Area labelled X is Greenland(Denmark). The Greenland biome is primarily characterized by a tundra biome with a central polar ice cap.
Correct answer: tundra- A. Population
- B. Species
- C. Community
- D. Biosphere
Explanation: A population is a group of organisms of the same species that live in the same area at the same time.
Correct answer: Population- A. Crustose lichen
- B. Foliose-lichen
- C. Moss
- D. Herbaceous
Explanation: In this stage the lichens are just like crumpled leaves attached at one point.
Correct answer: Foliose-lichen- A. Wild life
- B. Lichens
- C. Herbs
- D. Forest
Explanation: Forests are complex ecosystems characterized by dense vegetation, including trees, shrubs, herbs, and understory plants.
Correct answer: Forest- A. There are two producers and three herbivores.
- B. There are two primary consumers and two secondary consumers.
- C. There are three producers and two primary consumers.
- D. There are two herbivores and two tertiary consumers.
Explanation: It is correct because there is 2 producers which are phytoplankton and seaweeds and 3 herbivores which eat them.
Correct answer: There are two producers and three herbivores.- A. A
- B. B
- C. C
- D. D
Explanation: D shows denitrification. Denitrification is a microbial process in which nitrate (NO₃⁻) is converted back into nitrogen gas (N₂) or…
Correct answer: D- A. Xerach
- B. Secondary
- C. Hydrarch
- D. Primary
Explanation: Secondary succession happens when a climax community or intermediate community is impacted by a disturbance.
Correct answer: Secondary- A. Ammonification
- B. Assimilation
- C. Nitrification
- D. Denitrification
Explanation: Denitrification is the process that converts nitrate to nitrogen gas, thus removing bioavailable nitrogen and returning it to the…
Correct answer: DenitrificationEcosystems MCQs: common questions
Are these Ecosystems MCQs free?
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How many Ecosystems MCQs are on this page?
There are 69 Ecosystems MCQs in the Biology bank, shown 20 to a page with the correct answer and an explanation on each.
Does every Ecosystems MCQ have an explanation?
Yes. Each Ecosystems question shows the correct option and a written explanation of why it is correct, so a wrong answer teaches you something rather than just being marked wrong.
Can I take a timed Ecosystems test?
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