Meiosis

At meiosis, when haploid gametes are formed from a diploid adult, an additional process called recombination occurs. The pair of chromosomes physically line up and swap genetic material.

• Recombination shuffles the combinations of genes.

• Recombination is a random process; it may or may not 'hit' any point in the DNA. It occurs with a given probability, usually symbolized by r between any two points on a chromosome.

Meiosis is a process of replication and division, conservatism and new variation which is easiest to understand when described graphically: an animation demonstrates the process.

Figure: recombination at the gene level: the gene sequence in chromosome 1 changes from ABC to ABc.