Meiosis

sexual reproduction

sexual reproduction

reproduction that results from combining genetic material from two parents.

meiosis

type of cell division that results in 4 daughter cells that each have half the number of chromosomes as the parent cell.

homologous pairs

A pair of chromosomes of similar size and shape, one from each parent containing same genes.

Diploid

A cell containing two full sets of chromosomes (one from from each parent).

Haploid

A cell containing a single set of chromosomes

Gametes

A haploid sex cell

Sperm

Male sex cell

Egg

Female sex cell.

2n

Symbol for diploid number of chromosomes in a cell.

1n

Symbol for haploid number of chromosomes in a cell.

gene

a section of the DNA (chromosome) that codes for a specific trait (e.g. eye color or hair color)

crossing over

homologous chromosomes exchange genes during Prophase 1 creating genetic variation

Meiosis I

The first series of cell division of meiosis when the homologous pairs are split up into two separate cells.

Meiosis II

The second series of cell division of meiosis. Sister chromatids are split up into two separate cells.

zygote

the result of a sperm and an egg coming together during fertilization.

Cytokinesis

The last phase after Telophase when cytoplasm divides.

Mitosis

Produces two genetically identical daughter cells with diploid number of chromosomes

Asexual reproduction

One parent. Has the advantage of producing offspring in greater numbers.

Tetrad

Structure made of a pair of homologous chromosomes each composed of sister chromatids

Synapsis

Pairing of homologous chromosomes in Prophase I

Disjunction

The separation of chromosomes during Anaphase

Genetic Variation/Independent assortment

Arises from crossing over and random separation of chromosomes during meiosis

How are meiosis and mitosis similar?

DNA is replicated in interphase, Follows all the same phases PMAT, Starts with one parent cell.

How do meiosis and mitosis differ?

Mitosis results in 2 diploid cell and meiosis results in 4 haploid cells. Meiosis has genetically different daughter cells while mitosis has identical daughter cells. Meiosis has crossing over to recombine genes while mitosis has no recombination of genes. Mitosis produces somatic cells(body) and meiosis produces gametes(sex cells). Meiosis has two divisions while mitosis has one division.

The process by which sperm is made is called

spermatogenesis

The process by which eggs are made is called

oogenesis

When a sperm and egg combine, it is called

fertilization