B1 Genes

Oragnisms of the same species will look different. They're called variation within a species, two types of variation: genetic variation and environmental variation.

• Plants and animals have characteristics that are similar to their parents', this is because an organism's characteristics are determined by the genes inherited by its parents.
• These genes are passed on in gametes which the offspring develop from.
• They get some genes from the mother and some from the father and this combining of genes makes genetic variation, no two of the same species are genetically idenical, except identical twins.
• Some characteristics are determined only by genes eg the flower colour of a plant or the eye colour, blood group or inherited disorders in animals.

The environment can also cause differentiation between members of the same species, called environmental variation. It covers a wide range of variation such as losing your toes in a piranha attack or getting a suntan or a plant having yellow leaves. Any difference that has been caused by the contitions that something lives in.

Most characteristics are due to genetics AND the environment.