In the following food chain, grass provides 4000 j of energy to the grasshopper. How much energy will be available to snakes and frogs?

Grass, Grasshopper, Frogs, Snakes

In the following food chain, 100 j of energy is available to the lion. How much energy was available to the producer?

What is meant by non-biodegradable waste? Identify biodegradable waste from the following:

Empty packet of chips, empty plastic bottle of mineral water, empty paper box of sweets, empty tin of a cold drink.

Name the group of chemical compound which adversely affects the ozone layer.

In which form do the plants store the trapped solar energy?

Pesticides added to the field is seen in increased amounts in the crop and in the birds that feed on them. What is the phenomenon called?

Why is a lake considered to be a natural ecosystem?

Differentiate between biodegradable and non-biodegradable substances. Cite examples.

Why do all food chains start with plants and have a limited number of tropic levels?

What is ozone? Name the chemicals that damage the ozone layer.

Why is excessive use of chlorofluorocarbons a cause of concern?

Name the organism (s) belonging to fourth trophic level in the food chain comprising of snakes, insects, frogs, plants, hawks.

Mention the role of microorganisms like bacteria and fungi in the ecosystem.

Suggest suitable mechanism(s) for waste management in fertiliser industries.

(a) Why are green plants called producer?

(b) State the scientific term used for progressive accumulation of harmful chemicals at each trophic level of a food chain.

We do not clean ponds or lakes, but an aquarium needs to be cleaned. Why?

“Energy flow in food chains is always unidirectional.” Justify this statement. Explain how the pesticides enter a food chain and subsequently get into our body.

Suggest any four activities in daily life which are eco-friendly.

Differentiate between food chain and food web.

What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?

(a) Draw a line diagram to show flow of solar energy in ecosystem.

(b) Why is the government stressing upon the use of jute/cloth carry bags?

(c) List any two artificial ecosystems.

(a) Which gas shields the surface of the earth from the harmful UV-radiations from the sun?

(b) Mention one example each of biotic and abiotic components of ecosystem.

(c) Identify which one of the following would have hazardous impact if it persists in the environment for a long time. Plastic, vegetable waste, steel utensils