Meosis

Genes

The code for the formation of proteins, which carry out most of the work for cells.

Homologous Chromosomes

Chromosomes that carry the same genes and control the same traits and that make up a pair, which is one from each parent.

Gametes

Sex cells (sperm and egg) Each have 23 chromosomes.

Haploid cells

These have one set of chromosomes

Diploid cells

These have two sets of chromosomes

Sex chromosomes

1 pair of the 23 pairs of chromosomes in a human cell determines an individual’s gender. An individual with two X chromosomes is considered female. An individual with one X chromosome and one Y chromosome is considered male.

Autosomes

Other 22 pairs of chromosomes that are not sex chromosomes.

Prophase 1

1. Pairing of homologous chromosomes occurs, each chromosome consists of two chromatids.

2. Crossing over produces exchange of genetic information

3. Nuclear envelope breaks down

4. Spindle fibers form.

Crossing over

The process by which chromosomal segments are exchanged between a pair of homologous chromosomes.

Synapsis

The homologous chromosomes are held tightly together along their lengths.

Metaphase 1

1. Chromosomes attach to spindle fibers

2. Homologous chromosomes line up at the equator

Anaphase 1

1. Homologous chromosome separate and move to opposite poles of the cells.

Telophase 1

1. The spindles break down

2. Chromosomes uncoil and form two nuclei

3. Cell divides

Prophase II

1. Chromosomes condenses

2. Spindle forms in each new cell

3. Spindle fibers attach to chromosomes

Metaphase II

1. Centromeres of chromosomes line up randomly at the equator of each cell.

Anaphase II

1. Centromeres split

2. Sister chromatids separate and move to opposite poles.

Telophase II

1. Four Nuclei forms around chromosomes

2. Spindles break down

3. Cell divides

Products

1. Four daughter cells are made

2. Each nuclei has a haploid number of chromosomes.

Mitosis vs Meiosis

He I’m too lazy go read the book !

Telomeres

Protective caps that chromosomes end in

Karyotype

Pairs of homologous chromosomes that are arranged in decreasing size to produce a micrograph.

Nondisjunction

Cell division in which sister chromatids fail to separate properly.

Cellular differentiation

The process by which an unspecialized cell develops into a specialized cell with a defined structure and function.

Stem cell

Type of cell that can be directed to become a specialized cell.