Genetics

Chromosomes are made from DNA. Genes are short sections of DNA. DNA carries genetic code that determines characteristics of a living organism.

All cells have a cell cycle, where they grow, copy their DNA, and spilt into new cells during cell division. What are the two types of cell division?

Genetic diagrams show how characteristics are inherited. Alleles can be recessive, dominant or codominant genes.

Sex is controlled in humans by the X and Y chromosomes. Genetic screening involves testing people for the presence of genetic abnormality.

Genetic engineering is a process that modifies the genome of an organism to introduce desirable characteristics.

Organisms of the same species vary in many ways. There are two types – continuous and discontinuous. Natural selection explains how evolution occurs.