Multiple Choice Questions (MCQs)
Instruction: Select the correct option for each question.
- What is a habitat?
a) Only the place where animals hunt
b) The place and conditions where an organism lives and survives
c) A community of only plants
d) Only the climate of an area
Answer: b) The place and conditions where an organism lives and survives
A habitat provides food, water, shelter, space, and suitable abiotic conditions. - Which pair correctly shows biotic and abiotic components?
a) Soil (biotic), fish (abiotic)
b) Sunlight (biotic), bacteria (abiotic)
c) Tree (biotic), sunlight (abiotic)
d) Frog (abiotic), air (biotic)
Answer: c) Tree (biotic), sunlight (abiotic)
Living organisms are biotic; non-living factors like light, air, water are abiotic. - A population is best defined as:
a) All living and non-living things in an area
b) Different species living together
c) Members of the same species in a given area and time
d) All plants in all habitats
Answer: c) Members of the same species in a given area and time
Population counts individuals of one species in a defined space and time. - Pollination is the transfer of:
a) Seeds from fruit to soil
b) Pollen from stamen to carpel
c) Roots to shoots
d) Water to leaves
Answer: b) Pollen from stamen to carpel
Pollination enables fruit and seed formation. - Which sequence correctly shows a food chain?
a) Snake → Eagle → Grasshopper
b) Grass → Hare → Tiger
c) Eagle → Snake → Frog → Grasshopper
d) Frog → Grass → Grasshopper
Answer: b) Grass → Hare → Tiger
Energy flows from producer to herbivore to carnivore. - Decomposers like mushrooms and bacteria are important because they:
a) Produce seeds
b) Make sunlight
c) Break down dead matter and recycle nutrients
d) Stop plant growth
Answer: c) Break down dead matter and recycle nutrients
They return nutrients to soil, preventing waste buildup. - In the pond example, removing fish can lead to less plant pollination because:
a) Fish pollinate flowers directly
b) Fish eat pollinators
c) Dragonflies increase and reduce pollinators, lowering pollination
d) Plants stop growing without fish
Answer: c) Dragonflies increase and reduce pollinators, lowering pollination
This shows cascading effects in a community. - Producers in an ecosystem are:
a) Animals that hunt
b) Plants that make food by photosynthesis
c) Fungi that decompose
d) Humans only
Answer: b) Plants that make food by photosynthesis
Producers form the base of food chains and pyramids. - Which interaction benefits both partners?
a) Parasitism
b) Competition
c) Mutualism
d) Predation
Answer: c) Mutualism
Example: bees and flowers; both gain. - Why are mangroves like the Sundarbans valuable?
a) Only for tourism
b) They reduce floods, store carbon, and support biodiversity
c) They increase storms
d) They have no role in fisheries
Answer: b) They reduce floods, store carbon, and support biodiversity
Mangroves protect coasts and are rich ecosystems.
Fill in the Blanks
Instruction: Fill in the blanks with the correct word based on the chapter.
- The living parts of a habitat are called __________ components.
Answer: biotic
Include plants, animals, and microbes. - The non-living parts like air, water, soil, and light are __________ components.
Answer: abiotic
They influence survival and distribution. - A group of different populations living and interacting in one area is called a __________.
Answer: community
Includes all biotic components. - Plants are called __________ because they make their own food.
Answer: producers (autotrophs)
They convert sunlight into chemical energy. - Organisms that eat both plants and animals are called __________.
Answer: omnivores
Example: fox, mouse (depending on diet). - Interconnected feeding relationships form a __________.
Answer: food web
More realistic than a single chain. - Organisms like fungi and bacteria that break down dead matter are called __________.
Answer: decomposers (saprotrophs)
They recycle nutrients back to the soil. - The position of an organism in a food chain is its __________ level.
Answer: trophic
Producers are first trophic level. - Cutting too many trees and pollution can disturb __________ balance.
Answer: ecological (ecosystem)
Large disruptions harm stability. - Areas like national parks and sanctuaries are set aside as __________ areas.
Answer: protected
They conserve habitats and wildlife.
Very Short Answer Questions
Instruction: Answer the following questions in one line.
- Define habitat.
Answer: The place and set of conditions where an organism lives and survives. - What is pollination?
Answer: Transfer of pollen from stamen to carpel to enable seed and fruit formation. - Name the three main consumer types.
Answer: Herbivores, carnivores, and omnivores. - Who are decomposers? Give one example.
Answer: Organisms that break down dead matter; example: mushrooms (fungi) or bacteria. - What is one role of migratory birds?
Answer: They act as pollinators and seed dispersers linking distant habitats.
Short Answer Questions
Instruction: Answer the following questions in 2–3 lines.
- How are biotic and abiotic components linked in an ecosystem?
Answer: Abiotic factors like sunlight, water, and soil enable plants to grow; plants feed animals; decomposers return nutrients to soil—forming a continuous cycle linking living and non-living parts. - Why does diversity in a habitat help maintain balance?
Answer: Many species use resources differently (time, place, food), reducing competition and stabilizing populations through food webs and checks and balances. - Explain the pond cascade when fish are removed.
Answer: Fewer fish → more dragonflies (their larvae survive) → fewer pollinators (eaten by dragonflies) → less pollination → reduced plant seed set and growth. - How do mangroves protect coasts and climate?
Answer: Their roots slow waves and storm surges, reducing floods, and their trees store carbon and support rich biodiversity. - Why can overuse of pesticides harm farms long-term?
Answer: It kills helpful soil organisms and natural predators, reduces humus and soil fertility, can create resistant pests, and harms pollinators needed for crops.
Match the Following
Instruction: Match Column A with the correct option in Column B.
- Column A:
1) Producer
2) Decomposer
3) Mutualism
4) Trophic level
5) Protected area - Column B:
a) Relationship where both partners benefit (e.g., bees–flowers)
b) Position of an organism in a food chain
c) National park/sanctuary conserving habitats
d) Plant making food via photosynthesis
e) Mushroom/bacteria recycling nutrients
Correct Matches:
- Producer — d) Plant making food via photosynthesis
Explanation: Plants form the base of energy flow. - Decomposer — e) Mushroom/bacteria recycling nutrients
Explanation: They break down dead matter and return nutrients to soil. - Mutualism — a) Relationship where both partners benefit (e.g., bees–flowers)
Explanation: Pollinators get nectar; plants get pollinated. - Trophic level — b) Position of an organism in a food chain
Explanation: Indicates step in energy transfer. - Protected area — c) National park/sanctuary conserving habitats
Explanation: Legal protection helps biodiversity survive.