Inheritance and variation GapFill

 MiescherMendelPasteurDarwin, and his work using pea plants, formed the basis of what we know as inheritance, though his ideas were not accepted until long after he died. He suggested the idea of units of inheritance, which later became known as  allelesgenomeschromosomesPunnett squares.

The term  genomeproteomePunnett squareallele is used to describe the complete sequence of DNA in cells. Characteristics, such as hair colour and height, might be controlled by one or more genes, each of which can have multiple different forms, known as  chromatidsisotopesallelesheterozygotes. If two identical copies exist in an individual, they are described as  dominantheterozygoushomozygousrecessive. If both copies are required for the trait to be expressed, then the term  homozygousheterozygousdominantrecessive is used.

In order to predict the outcome of two organisms mating, a  family treePunnett squarerecessive rectangleDarwin ladder can be drawn, which gives estimated proportions of individuals. 

 VariationMutationDifferentiationSpecialisation is a term used widely in biology to describe the amount of difference seen between organisms of either the same or different species. This can be due to genes,  proteinsappearancebreedingthe environment or a combination of both. Within a population of a single species, there is normally  recessiveextensivelittledominant genetic variation as a result of  polymerisationrespirationmutationphotosynthesis, and this can often lead to the basis of evolution. However, these genetic changes do not always lead to changes in an organism's  zygotegenotypephenotypechromosome – most have either no effect or only a small effect.