Evolution Of Species

Question 1

Define a mutation

Answer 1

A mutation is a random change to genetic material

Question 2

How would you describe a mutation?

Answer 2

They are spontaneous and are the only source of new alleles.

Question 3

What 3 things may mutations confer?

Answer 3

1. Advantage
2. Disadvantage
3. Neutral

Question 4

What environmental factor can increase the rate of mutation?

Answer 4

Exposure to radiation

Question 5

Define adaptation

Answer 5

A physical or behavioural change of an organism to make it best suited to its environment

Question 6

Give 2 adaptations of a cactus

Answer 6

1. Their leaves are reduced to spines to prevent water loss.

2. They have long roots to reach underground water.

Question 7

Give 2 adaptations of the fennec fox

Answer 7

1. It’s nocturnal meaning it is only active at night when it’s cooler.
2. They have large ears which helps it to hear underground prey.

Question 8

Species produce more offspring than the environment can sustain. Give 3 examples why many of the offspring die due to selection pressures

Answer 8

1. Predation
2. Food shortage
3. Lack of resistance to disease

Question 9

What is natural selection?

Answer 9

The organisms best adapted to their environment will survive and reproduce, passing their favourable alleles to the next generation. Those not suited will die before reaching reproductive age.

Question 10

What is speciation?

Answer 10

The formation of new species

Question 11

When does speciation occur?

Answer 11

When a population becomes isolated from other members of its species for a very long time or perminantly

Question 12

What are the three types of barriers which may prevent interbreeding and exchange of genetic material

Answer 12

1. Geological
2. Economical
3. Reproductive