meiosis - production of gametes

Sex chromosomes

Determine the sex of an individual. Females XX Males XY

Automes

Non sex chromosomes. 44 autosome chromosomes 2 sex chromosomes

Sister chromatids

When a chromosome replicates it forms 2 sister chromatids joined at a centromere

Homologous chromosomes

Two chromosomes that carry the same genes. Same size and shape. Together make a homologous pair

Paternal chromosomes

Chromosomes inherited from father

Maternal chromosomes

Chromosomes that you have inherited from mother

Haploid

One set of chromosomes. The haploid number is the number of chromosomes in the one set eg. in humans is 23

Gametes

Sex cell produced by meiosis. Males sperm . Female eggs.

Male sex cell in plant?

Pollen

Meiosis

Cell division producing gametes. One diploid cell divides to produce four haploid cells.

Meiosis starting is

DNA replication occurs. Making an identical copy joined at a centromere and are sister chromatids

Prophase of meiosis

Homologous pair form and line up and cross over occurs to share variations

Metaphase of meiosis

Sister chromatids met in the middle

Anaphase of meiosis

Homologous pairs seperate

Tolophase of meiosis 1

Cytoplasm has divided producing 2 new cells.

Meiosis 2 metaphase

Sister chromatids will pull apart forming 2 cells.

Meiosis 1

Pull homologous pairs apart

Meiosis 2

Pull sister chromatids apart

Three differences between mitosis and meiosis.

Mitosis produces cells for growth and repair. Meiosis produces gametes for sexual reproduction.

Mitosis produced diploid cells. Meiosis produces haploid cells by halving the chromosome number.

Mitosis produces identical cells. Meiosis produces variation in cells through the process of independent and random assortment and crossing over.