9.1 Interdependence

What is the area where a polar bear lives called?

• the igloo

• the desert environment

• the Arctic habitat

• the winter habitat

Examples of physical environmental factors that make up an environment include:

• temperature, light, moisture

• producers, consumers

• herbivores, carnivores, omnivores

• Arctic, woodland, pond.

An ecosystem is:

• plumbing and wiring in a house that uses less water and energy than older systems

• all the different physical environmental factors that affect a habitat

• all the different types of organisms in a habitat

• all the organisms in a habitat together with the physical environmental factors.

What does a rabbit do when winter comes?

• it hibernates

• it grows thicker fur

• it migrates

• it dies

At a certain lake, the community is smaller in winter because:

• some of each species of animal have died

• some species of birds have migrated

• more animals have arrived for the winter so that they can keep warm together

• there is more ice on the lake and so less room for the organisms.

A herbivore:

• only eats animals

• eats plants and animals

• never eats

• only eats plants.

Look at this food web. What do lizards eat?

• mice

• grasshoppers

• hawks

• grass

What resources do plants need?

• oxygen, food

• fertiliser, a garden, water

• light, space, water, mineral salts

• weedkiller

Look at the food web. What might happen if all the rabbits died?

• There would be more hawks because there are less rabbits in competition with them.

• There would be fewer lizards because the hawks would eat more of them.

• There would be less grass because it would be eaten by the grasshoppers.

• There would be more snakes because they would not be in competition with the rabbits.

What is a pesticide?

• a type of fertiliser used by farmers

• a type of food for small animals

• an animal that eats crops

• a chemical that kills organisms that ruin things that humans want