B12-14 Extra

Question 1

What is variation

Answer 1

Variation is the differences in characteristics of individuals in a population/species

Question 2

What can variation be caused by

Answer 2

Variation can be caused by : the genes a person inherits (genetic causes )

• The environment a person lives in/grew up in (environmental causes)
• A mixture of genetic and environmental causes

Question 3

What is evolution

Answer 3

Evolution is the change in inherited characteristics of a population over time through a process of natural selection which may result in the formation of a new species

Question 4

Describe Darwins theory of natural selection

Answer 4

• In a species all individuals are different and show a wide range of variation
• This variation is because of differences in their genes (continous mutations)
• Individuals with characterists most suited to the environment (have ab advantage )are more likely to survive and reproduce
• The genes/alleles that allowed these individuals to be succesful are then passed onto their offspring

Question 5

Why did people not believe Darwin

Answer 5

• Darwins theory challenged the idea that God made all living things on earth
• There was insuffient evidence at the time his theory was published to convice scientists at the time
• The mechanism of inheritance/genes was not known until 50 years after Darwins theory had been published