Meiosis and Sexual Life Cycles

These flashcards cover key vocabulary and concepts related to meiosis and sexual life cycles, as described in the lecture notes.

Meiosis

A type of cell division that produces haploid gametes from diploid parent cells.

Diploid (2n)

A cell or organism with two sets of chromosomes, one from each parent, totaling 46 chromosomes in humans.

Haploid (n)

A cell or organism with one set of chromosomes, totaling 23 chromosomes in humans.

Homologous chromosomes

A pair of chromosomes containing the same genes, one inherited from each parent.

Gametes

Reproductive cells (sperm and eggs) that carry half the genetic information of an organism.

Karyotype

An ordered display of the pairs of chromosomes from a cell.

Crossing over

The exchange of genetic material between homologous chromosomes during prophase I of meiosis.

Independent assortment

The random distribution of maternal and paternal chromosomes into gametes.

Zygote

The fertilized egg formed when a sperm and egg combine.

Genetic variation

Differences in alleles among individuals, resulting from processes like crossing over and independent assortment.

Nonsister chromatids

Chromatids of homologous chromosomes that are not identical and can undergo crossing over.

Alleles

Different versions of a gene that may produce distinguishable phenotypic effects.

Cohesins

Proteins that hold sister chromatids together until they are separated during cell division.

Chiasmata

X-shaped structure formed during crossing over where homologous chromosomes exchange genetic material.

Fertilization

The union of male and female gametes to form a zygote.