Unit 1-Life On Earth

Question 0

What is a community?

Answer 0

All the populations of different species that live together in a habitat

Question 1

What is a population?

Answer 1

All the members of a single species that live in a habitat.

Question 2

What is a habitat? Give an example.

Answer 2

The place where an organism lives. An example of a habitat is a tree in a forest.

Question 3

What is an ecosystem?

Answer 3

A community and the habitat in which it lives.

Question 4

What is a niche?

Answer 4

A Niche is the role an organism plays within a community.

Question 5

What is a biome?

Answer 5

A biome is a large area of ecosystem

Question 6

How can biomes be influenced?

Answer 6

Global distribution of biomes can be influenced by temperature and rainfall.

Question 7

What is a food chain? Give an example.

Answer 7

A food chain shows what eats what in a habitat. An example of a food chain is:
Grass growing-> mouse eats grass-> owl eats mouse.

Question 8

What does a pyramid of numbers represent?

Answer 8

A pyramid of numbers represent the number of organisms at each stage in a food chain.

Question 9

What does a pyramid of biomass represent?

Answer 9

A pyramid of biomass represents the mass of an organism at each stage in a food chain.

Question 10

What does a pyramid of energy represent?

Answer 10

A pyramid of energy represents the energy of an organism at each stage in a food chain.

Question 11

How much energy is passed on along a food chain?

Answer 11

10% of energy is passed on along a food chain.

Question 12

How much energy is lost along a food chain? How?

Answer 12

90% of energy is lost along a food chain. It is lost through heat, movement and undigested materials.

Question 13

What may animals have to compete for in their habitat?

Answer 13

Animals may have to compete for space, food, water and mates.

Question 14

What may plants have to compete for in their habitat?

Answer 14

Plants may have to compete for light, space, minerals and water.

Question 15

Give the definition of interspecific competition.

Answer 15

Interspecific competition is when individuals from a different species compete for the same resources in an ecosystem.

Question 16

Give the definition of intraspecific competition.

Answer 16

Intraspecific competition is when individuals from the same species compete for the same resources in their ecosystem.

Question 17

What is a mutation?

Answer 17

A mutation is a random change in genetic material

Question 18

What can cause a mutation to speed up?

Answer 18

An exposure to radiation can speed up a mutation.

Question 19

What are the only source of new alleles?

Answer 19

A mutation

Question 20

What is natural selection?

Answer 20

Natural selection occurs when more offspring are produced than the ecosystem can support.

Question 21

What is a producer?

Answer 21

A producer is an organism that makes its own food. E.g. Grass or any green plant.

Question 22

What is a primary consumer?

Answer 22

A primary consumer is an organism that eats plant material.

Question 23

What is a secondary consumer?

Answer 23

A secondary consumer eats animal material such as cats, dogs of lions.

Question 24

What is a predator?

Answer 24

A predator is an organism that kills other organisms for food. They are usually secondary or tertiary consumers.

Question 25

What is a prey?

Answer 25

A prey is the organism that a predator hunts.

Question 26

What is a scavenger?

Answer 26

A scavenger is an organism that feeds on the bodies of dead animals such as crows, vultures and hyenas.

Question 27

What is a decomposer?

Answer 27

A decomposer feeds on dead and decaying organisms and on the undigested parts of plant and animal matter in faeces.

Question 28

Give the definition of a disadvantageous mutation and an example.

Answer 28

The changes in a disadvantageous mutation can be so severe that the organism dies or have severe disorders.