18.2

Question 1

What do individuals of the same species show?

Answer 1

Individuals within a population of the same species show a wide range of variation in their phenotype.

Question 2

Why is there a variation?

Answer 2

Due to environmental and genetic factors.

Question 3

What are causes of variations?

Answer 3

Primary source of genetic variation is mutation and further genetic variation may occur due to meiosis or random fertilisation of gametes during sexual reproduction

Question 4

Why does genetic variation arise?

Answer 4

1. Mutations: sudden changes to genes/chromosome may or may not be passed on to the next generation
2. Meiosis: nuclear division produces new combination of alleles before passed into gametes
3. random fertilisation of gametes: Sexual reproduction produces new combination of alleles and offspring are different from parents

Question 5

what graphs are used for genetic and environmental factors

Answer 5

• Environmental factors: line graph, mean calculated normal distribution curve
• genetic factors: bar chart