How Nature Works in Harmony — Class 8 MCQs with Answers

How Nature Works in Harmony — important questions & MCQs with answers (Class 8 Science)

6 solved questions from this chapter's difficulty levels, each with its answer and explanation. Tap an option to check yourself.

0 of 6 answered

1. Q1 of 6Easy

   The place where an organism lives is called its:

   AhabitatBecosystemCfood chainDpopulation
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   Answer: habitat

   Explanation: A habitat is the specific place where an organism naturally lives, such as a pond for a fish or a tree hollow for an owl.

2. Q2 of 6Easy

   Which of these is a biotic (living) component?

   AsunlightBa plantCwaterDsoil
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   Answer: a plant

   Explanation: A plant is a living organism, so it counts as a biotic component; sunlight, water and soil are non-living, abiotic factors.

3. Q3 of 6Medium

   In the food chain grass → grasshopper → frog → snake, the producer is:

   AgrassBgrasshopperCfrogDsnake
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   Answer: grass

   Explanation: In grass → grasshopper → frog → snake, grass is the producer because it makes its own food through photosynthesis.

4. Q4 of 6Medium

   If there were no decomposers, dead bodies and waste would:

   Avanish instantlyBpile up and nutrients would not return to the soilCturn into plantsDhave no effect
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   Answer: pile up and nutrients would not return to the soil

   Explanation: Without decomposers, dead bodies and waste would pile up because nutrients would never be returned to the soil.

5. Q5 of 6Hard

   A habitat differs from an ecosystem in that a habitat is:

   Aexactly the same as an ecosystemBjust the place an organism lives, while an ecosystem includes all living and non-living interactionsConly the animalsDonly the Sun
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   Answer: just the place an organism lives, while an ecosystem includes all living and non-living interactions

   Explanation: A habitat is simply the place an organism lives, while an ecosystem is the whole web of living and non-living interactions in that place.

6. Q6 of 6Hard

   Which set lists only abiotic components?

   Aair, water, sunlight, soilBfish, frogs, plantsCbacteria, fungiDdeer, grass, tiger
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   Answer: air, water, sunlight, soil

   Explanation: Air, water, sunlight and soil are all non-living, so together they form a set of purely abiotic components.

How Nature Works in Harmony notes: key concepts (Class 8 Science)

This chapter shows how living and non-living things work together in nature. The place an organism lives is its habitat, and an ecosystem is the whole set of biotic (living) and abiotic (non-living) components interacting. Green plants are producers that make food by photosynthesis; consumers (herbivores, carnivores and omnivores) eat other organisms; and decomposers such as bacteria and fungi break down dead matter and recycle nutrients. Food chains show who eats whom, food webs link many chains, and energy flows from the Sun through producers to consumers — keeping nature in a delicate balance that human overuse of resources can easily disturb.

Habitat

The place where an organism lives, providing it with the conditions it needs, such as a pond, a forest or a grassland.

Ecosystem

All the living and non-living components of an area interacting together; a pond or a forest is an ecosystem.

Population and community

A population is all the individuals of one species in a habitat; a community is all the different populations living together.

Biotic components

The living parts of an ecosystem — plants, animals and microbes.

Abiotic components

The non-living parts of an ecosystem — air, water, soil, sunlight and temperature.

Producers

Green plants (autotrophs) that make their own food by photosynthesis, using sunlight, water and carbon dioxide; they bring energy into the ecosystem.

Consumers

Organisms that depend on others for food: herbivores eat plants, carnivores eat animals, and omnivores eat both.

Decomposers

Bacteria and fungi that break down dead plants and animals into simpler substances, recycling nutrients back to the soil for producers to reuse.

Food chain and trophic levels

A food chain is a sequence of who eats whom, with producers at the first level; the feeding positions are called trophic levels.

Food web

Many interconnected food chains, which is more realistic because most animals eat more than one kind of food.

Energy flow

Energy flows from the Sun to producers and then to consumers, decreasing at each higher level, so there are fewer top carnivores than plants.

Balance in nature

Living and non-living parts are interdependent; removing a group, such as decomposers or a top predator, upsets the balance, which human overuse of resources can also disturb.