What is fertilization?

• the union of two haploid cells typically from two individual organisms

What is meiosis?  Which cells are produced by meiosis?

• a nuclear division process that results in four haploid cells

• The process of meiosis produces genetically unique reproductive cells called gametes which have half the number of chromosomes as the parent cell

What is the ploidy (haploid or diploid) of gametes (sperm and eggs)?

• Gametes are Haploid

Describe the phases of meiosis I and the major events of each phase:

• Prophase I:

• Metaphase I:

• Anaphase I:

• Telophase I:

Is the nucleus haploid or diploid at the beginning of Meiosis I? Is it haploid or diploid at the end of Meiosis I?

• Diploid

• Haploid

Describe the phases of meiosis II and the major events of each phase:

• Prophase II:

• Metaphase II:

• Anaphase II:

• Telophase II:

Is the nucleus haploid or diploid at the beginning of Meiosis II? Is it haploid or diploid at the end of Meiosis II?

• Haploid

• Haploid

What is crossing over?  During which stage of meiosis does crossing over occur?  What is the significance of crossing over?

• (also, recombination) the exchange of genetic material between homologous chromosomes resulting in chromosomes that incorporate genes from both parents of the organism forming reproductive cells

• Prophase I

• It creates new gametes → new genes

What is independent assortment?  During which stage of meiosis does independent assortment occur?  What is the significance of independent assortment?

• How different genes independently separate from one another when reproductive cells develop

• Metaphase I

• Responsible for the production of new genetic combinations in the organism along with crossing over

Compare and contrast mitosis and meiosis.  What are the similarities in these two processes?  What are the differences?

• Mitosis produces two genetically identical “daughter” cells from a single “parent” cell

• Meiosis produces cells that are genetically unique from the parent and contain only half as much DNA

• Most cells in the body regularly go through mitosis, but some do so more often than others.