KA6- Evolution Of Species

Question 1

Mutation

Answer 1

Random change in the DNA of an organism
Can cause a change in the appearance (phenotype) of an organism
May result in a protein not working properly

Question 2

Neutral mutations

Answer 2

Have no effect on phenotype
Change to the genetic sequence that still codes for the same amino acid

Question 3

Advantageous mutations

Answer 3

Mutations that are beneficial and improve survival chances
Survival benefits for phenotype
E.g peppered moth

Question 4

Disadvantageous mutations

Answer 4

Harmful mutations because they disturb the proper working of cells
Decreases survival of phenotype
E.g Down syndrome, cystic fibrosis

Question 5

Environmental factors that increase the rate of mutations/mutagens

Answer 5

Chemicals- mustard gas, benzene, colchicine
Radiation- gamma rays, UV light, x-rays, nuclear radiation

Question 6

Mutagen

Answer 6

Increase rate of mutations

Question 7

Gene

Answer 7

Small sections of DNA that control specific characteristics

Question 8

Alleles

Answer 8

Different variants of a gene

Question 9

Adaption

Answer 9

Inherited characteristic that makes the organism well suited in its environment

Question 10

Natural selection

Answer 10

Best adapted individuals in a population survive to reproduce, passing the favourable alleles that give a selective advantage
Over time these alleles increase in frequency within the population