Cell Division in Gamete Cells

MEIOSIS

Variation

If the cell cycle produces only exact copies, then how is their variation (variety, differences) among living things? Why is it that you look different from your parents and different from the other students in the room?

ANSWER: Meiosis and Crossing Over in Homologous Chromosomes

Homologous Chromosomes

Are corresponding chromosomes from the opposite-sex parent

Crossing OverA process occurring during meiosis wherein two

chromosomes pair up and exchange segments of their genetic material.

Ii important because it results in new combinations of genes that are different from either parent, contributing to genetic variation and diversity.

Crossing Over

Meiosis

Similar to mitosis in some ways but different in other ways.

In meiosis there are two different stages called:

Meiosis I Meiosis II

Meiosis I

Meiosis II

Meiosis

Meiosis produces four cells.

4 Haploid Gamete Cells

Meiosis and Egg Cells: OOGENESIS

Meiosis & Sperms Cells: SPERMATOGENESIS

A Comparison

MITOSIS & MEIOSIS

Cell Division

Mitosis Meiosis

Purpose Growth & Repair

Reproduction

Divisions 1 2

Parent Cell Diploid Diploid

Daughter Cells

2 diploids 4 haploids

Cell Type Somatic Gamete