Meiosis

Somatic Cells

All of the cells of an organism except your sex cells

Gametes

Cells involved in sexual reproduction

How many somatic cells are there?

46 chromosomes (23 homologous pairs)

How many sex cells are there?

23 chromosomes (no homologous pairs)

Locus

Location of a gene on a chromosome

Karyotype

Picture of chromosomes

Diploid

Contains two complete sets of chromosomes which are one from each parent

Asexual Reproduction

Produces offspring that are identical to the original cell from one parent

Sexual Reprodcution

Produces offspring that are similar to the parent, but involves inheritance of genes from two parents

How many chromosomes are in gametes?

23 chromosomes in sperm cell and 23 chromosomes in egg cell

Meiosis

Pairs of chromosomes split apart which produce gametes that have half the number of chromosomes (haploid)

Haploid

Cells that have one chromosomes from each pair

Synapsis

Chromosomes line up with its homologous pair

Crossing Over

Strands of the tetrad can sometimes twist and exchange segements between chromatids

Genetic Recombination

The production of new combiinations due to crossing over

Chiasma

Site of attachment and crossing over between nonsister chromatids

Prophase 1

Chromatin condenses and homologous pairs begin to align

Metaphase 1

Homologous pairs alingn in the ceneter

Anaphase 1

Homologous pairs separate (called disjunction)

Telophase 1

Chromosomes gather into nuclei, and the original cell divides (called cytokinesis)

Prophase 2

Cromosomes condense again

Metaphase 2

Chromatids align at center

Anaphase 2

Chromatids seperate to opposite poles

Telophase 2

Chromatids gather into nuclei and cells divide (cytokinesis)