An organism or cell reproduced asexually from the parent with no genetic variation.

Differences in offspring and parents due to sexual reproduction.

The creation of offspring with variation due to sperm and egg that fuse together.

The production of sperm or egg with half the normal number of chromosomes compared to normal body cells.

A sex cell produced in meiosis (sperm or egg) that has half the normal number of chromosomes:

23 chromosomes in humans.

A body cell with the normal number of chromosomes:

46 chromosomes in humans.

A gamete (egg) produced only in the ovaries of the female of a species.

Ova is plural.

A gamete produced only in the testicles of the male of a species.

Having the normal number of chromosomes and a matching set of each chromosome—one from each parent.

Example: Som­­atic cells, symbolized by 2n.

Having half the normal number of chromosomes and only one of each set due to meiosis. Example: Gametes, symbolized by the letter n.

A matching set of chromosomes

in a somatic cell: one from the mother and one from the father. Humans have 23 sets or 46 chromosomes in total in each cell.

Refers to each of the matching genes found in specific locations on homologous chromosomes: one allele from the mother and one allele from the father.

A photograph or diagram of the homologous pairs of chromosomes.

The first 22 pairs of chromosomes that do not determine the sex of an individual.

The 23^rd pair of chromosomes that determine the sex of an organism.

The larger of the two possible chromosomes that make up the sex chromosomes.

The smaller of the two possible chromosomes that make up the sex chromosomes. Found only in males.

Homologous pairs of chromosomes line up independently during meiosis, resulting in offspring that are a mix of maternal genes and paternal genes, increasing genetic variation.

Homologous pairs sometimes exchange alleles from the same locus during the first division of meiosis, increasing genetic variation.