Biology Unit 7 - Meiosis

What is Meiosis?

It is the process of reduction division in which the number of chromosomes per cell is cut in half throughout the separation of homologous chromosomes in a diploid cell.

What are the two different Meiotic divisions called?

Meoisis 1 and Meiosis 2.

How many daughter cells are produced that are haploid?

Four

What is a diploid number and what is a haploid number?

A diploid number is a term used to a cell that contains both sets of homologous chromosomes. A haploid cell that contains only a single set of chromosomes.

What is the production of egg cells called?

Oogenesis.

What is the production of sperm cells called?

Spermatogenesis.

Gametes

Gametes are egg and sperm.

Tetrads

Tetrads are the two homologous chromosomes that are attached together. Also called synapsis.

Name the different phases of Meiosis 1 in order.

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, and Interkinesis.

Name the different phases of Meiosis 2 in order.

Prophase 2, Metaphase 2, Anaphase 2, Telophase 2, and Cytokinesis.

Prophase 1

During Prophase 1, each chromosome pairs with its corresponding homologous chromosome to form a tetrad.

Metaphase 1

During Metaphase 1, spindle fibers attach to the chromosomes. The homologous chromosomes align at the equator of the cell.

Anaphase 1

During Anaphase 1, the fibers pull the homologus chromosomes toward opposite ends of the cell.

Telophase 1

During Telophase 1, nuclear membranes form, and the the cell separates into two genetically different cells.

Prophase 2

Nuclear envelope fragments, and the spindle forms.

Metaphase 2

Chromosomes align along the equator of the cell.

Anaphase 2

Sister chromatids separate and move to opp. poles of the cell.

Telophase 2 and Cytokinesis

the nuclear envelope assembles ad chromosomes decondenses and the spindle dissapears. Cytokinesis divides the cell into two, resulting into four haploid daughter cells.

Crossing-Over

means when homolgous chromosomes pair up and form tetrads and they exchange genetic information. And portions of their chromatids.

Genetic-Recombination

is the result of the exchange of alleles between homologous chromosomes which produces a new combination of alleles.

Homologous

A term used to refer to chromosomes that each have a corresponding chromosome from the opp. sex parent.

Chromatids

A chromatid is one of the two identical sister parts of a duplicated chromosome.

Alleles

One of the numbers of the different forms of a genes.

Somatic Cells

Body Cells