Every individual in the human population has different characteristics such as eye colour, height and body mass. Plants of the same species or type can also differ in height, flower colour or leaf length. These differences are called variation.

The version of a characteristic shown by an individual is called its phenotype.

Organisms that carry out sexual reproduction are able to combine different forms of genes from two parents, which increases variation in their offspring.

A phenotype is an inherited characteristic. The phenotype of every individual is due to the genes they inherited from their parents.


Characteristic: eye colour

Close up of two faces: one with blue eyes and one with brown eyes.
The variety of heights allowed with phenotypes in adults - 3 adults.  The first is 1.5 m tall, the second 1.7 m and the third 1.9 m.