Variation and evolution

Question 1

What causes variation in individuals and what can it lead to?

Answer 1

• Differences in our genes and environment can lead to huge variation between individuals and overtime, this can lead to evolution of a new species

Question 2

What is a phenotype?

Answer 2

• The observable characteristics within an individual due to interactions between its genes and the environment

Question 3

What is variation?

Answer 3

• All individuals in a population are different due to different phenotypes. This is known as variation

Question 4

Explain how mutation can lead to genetic variation

Answer 4

• Mutations don’t normally change proteins in our body. However, when they rarely do, they inturn change the genome of an individual and therfore, lead to genetic variation
• Mutations will rarely change the phenotype. If it does, it will usually be bad but can sometimes be beneficial

Question 5

Explain evolution by natural selection

Answer 5

• Proposed by Charles Darwin
• All individuals in a species are different due to genetic variation
• Beneficial mutations means an individual is more likely to survive
• Individual will reproduce and pass genotype of beneficial mutation onto offspring
• Repeats over multiple generations
• Leads to evolution of whole species

Question 6

Why did Darwin’s theory of evolution take so long to be accepted and how has it been proven since?

Answer 6

• Darwin’s theory took a very long time to be accepted due to a lack of evidence
• Since then, antibiotic resistance and fossil records (which show how a species has changed over time) have helped prove Darwin’s theory correct