B14.2 Evolution by natural selection

Question 1

What is natural selection?

Answer 1

Organisms that gain an advantage are more likely to survive and breed

Question 2

What is variation mainly caused by?

Answer 2

Meiosis

Mutation

Question 3

What is a mutation?

Answer 3

A change in the DNA code

Question 4

When can mutations take place?

Answer 4

Whenever the cells divide - the gametes may affect the phenotype and introduce new variants into the genes

Question 5

What is the theory of natural selection?

Answer 5

All species of living things have evolved from simple life forms - evolution through natural selection produces changes in the inherited characteristics of a population over time

Question 6

What is the full process of the survival of the fittest and evolution?

Answer 6

Individual organisms within a particular species may show genetic variation

Individuals with characteristics most suited to the environment are more likely to survive and breed successfully

The alleles are passed on

Question 7

How can you check if the population of a species is different?

Answer 7

If you try and interbreed them they can not form offspring due to them being infertile

Question 8

Use variation to explain why the population of oysters increased as the suffered from genetic variation?

Answer 8

There is variation among the oyster - due to mutations
Some oysters will have adaptions that are more suited for them to survive and breed successfully
The oysters reproduce
Offspring inherit the useful alleles
Explains increase from 1927 of the population of Oysters

Question 9

What is genetic variation?

Answer 9

New variant/form of a gene/new allele

resulting from change in organism’s DNA.