4.6.2.1 Variation

Question 1

Variation:

Answer 1

the differences in characteristics between individuals in a population due to genes, the environment or a combination of both

Question 2

What does the genome influence in an organism?

Answer 2

the genome and its interaction with the environment influence the development of the phenotype of an organism

Question 3

Processes that lead to genetic variation:

Answer 3

• meiosis
• sexual reproduction
• mutations

Question 4

Causes of variation:

Answer 4

1. Genotype
   
   1. the genes they have inherited (genetic causes)
   2. genes passed on from the parents in sex cells
   3. combining of genes from mother and father creates genetic variation
   4. identical twins have same genotype
   5. lots of genetic variation in a population
2. Environmental causes - the conditions in which they have developed in
3. Combination of genes and the environment

Question 5

What is there within a population?

Answer 5

usually extensive variation within a population of a species

Question 6

What do variants arise from?

Answer 6

• variants arise from mutations
• most mutations have no effect on the phenotype
• some influence phenotype
• very few determine phenoytype

Question 7

When do mutations occur?

Answer 7

• mutations occur continuously
• very rarely a mutation will lead to a new phenotype
• if the new phenotype is suited to an environmental change it can lead to a relatively rapid change in the species