B17 - Variation and Selection: AI

Question 1

What is variation? [2]

Answer 1

differences between individuals of the same species.

Question 2

What is continuous variation? [2]

Answer 2

results in a range of phenotypes between two extremes

Question 3

What is discontinuous variation? [2]

Answer 3

• results in a limited number of phenotypes with no intermediates

Question 4

What is mutation?

Answer 4

Mutation is a genetic change.

Question 5

How are new alleles formed?

Answer 5

Mutation is the way in which new alleles are formed.

Question 6

What is natural selection?

Answer 6

Natural selection involves genetic variation within populations, production of many offspring, struggle for survival, and better-adapted individuals having a greater chance of reproduction.

Question 7

What happens to individuals that are better adapted in natural selection?

Answer 7

Better-adapted individuals have a greater chance of reproduction and pass on their alleles to the next generation.

Question 8

What is an example of natural selection?

Answer 8

The development of strains of antibiotic-resistant bacteria is an example of natural selection.

Question 9

What is selective breeding?

Answer 9

Selective breeding involves humans selecting individuals with desirable features and crossing them to produce the next generation.

Question 10

How is selective breeding carried out?

Answer 10

Selective breeding is carried out over many generations to improve crop plants and domesticated animals.