Meiosis: sexual reproduction

Heredity and variationThe science of genetics

Parents pass on genetic information to offspring

• Genes (DNA)• Gametes- reproductive cells– haploid

• Somatic cells contain entire set of genes– diploid

Asexual vs sexual reproduction

• Asexual: offspring identical to (single) parent

• Sexual: offspring are combination from two parents

A diploid set of chromosomes

Properties of chromosomes

The human life cycle

…and others

Meiosis: chromosomal reduction

Meiosis vs mitosis

• Purpose• Types of cells• What type of cells and how many?• Behavior of chromosomes

Comparison of mitosis and meiosis (summary)

Sources of genetic variation: independent assortment

Crossing over

Summary

• Sexual reproduction increases genetic variation

• Asexual reproduction: offspring are identical to parents (except for mutation)

• Meiosis forms gametes: reductional division– Independent assortment– Crossing over– Mutation

• These fuse to form zygotes