Variation and Inheritance

Question 1

Variation

Answer 1

Sexual reproduction results in individuals with new combinations of genetic information. This means that although members of the same species are similar to one another, they are not identical to one another. Variations exist amongst members of the same species.

Question 2

Inheritance

Answer 2

Fertilisation is the fusion of the two haploid nuclei of the gametes to form a diploid zygote. Fertilisation is a random process. The zygote ends up with half its genetic complement from each parent. This is how characteristics are passed down through generations. This is called INHERITANCE.

Question 3

Type of Variation (Discrete) Single Gene

Answer 3

Where variation in a characteristic is clear cut with the organism belonging to one of two or more distinct groups. Examples of these include eye colour, blood groups, fingerprints.

Question 4

Type of variation (continuous) polygenic

Answer 4

This is where a characteristic of an animal or plant shows a wide range of variations between two extremes.

e.g. Height, hand span, weight, shoe size, tail length in mice, diameter of a shell, length of a leaf

Question 5

Graph for continuous variation

Answer 5

Bell shaped curve on a line graph or histogram.