B2(iii) - Genetics 7.

Genetic Diagrams.

In the exam they could ask about the inheritance of any kind of characteristic that's controlled by a single gene, because the principles always the same. 

Genetic Diagrams Show the Possible Genes of Offspring.

1) Alleles are different versions of the same gene.

2) Most of the time you have two copies of each gene one from each parent.

3) If they are different alleles, only one might be expressed in the organism. The characteristic that appears is coded for by the dominant allele. The other one is recessive.

4) In genetic diagrams letters are used to represent genes. Dominant…