Chapter 9 part 1 Meiosis and the Genetic Basis of Sexual Reproduction

Flashcards covering Meiosis and the Genetic Basis of Sexual Reproduction

Meiosis

A type of nuclear division that occurs as part of sexual reproduction in which the daughter cells receive the haploid number of chromosomes in varied combinations; division of the nuclear materials of germ cells.

Functions of Meiosis

Reducing chromosome number and shuffling chromosomes to produce genetically different gametes.

Homologous Chromosomes

Members of a pair of chromosomes with the same size, shape, and gene location.

Alleles

Alternate forms of a gene responsible for traits like eye color.

Autosomes

Any chromosome other than the sex-determining pair.

Life Cycle

Reproductive events that occur from one generation to the next in sexually reproducing organisms.

Somatic Cells

Body cells that are diploid (2n).

Gametes

Egg and sperm cells with only one member of each homologous pair (n).

Spermatogenesis

Produces sperm in the testes.

Oogenesis

Produces eggs in the ovaries.

Zygote

The diploid (2n) cell formed by the union of egg and sperm.

Synapsis

The pairing of homologous chromosomes during prophase I of meiosis.

Tetrad

The structure formed when homologous chromosomes pair up during synapsis, consisting of four chromatids.

Chiasma

The point where nonsister chromatids exchange genetic material during prophase I of meiosis.

Crossing-Over Significance

Increases variability of the gametes and, therefore, the offspring.