Meiosis and Sexual Reproduction

This set of flashcards covers key vocabulary and concepts related to meiosis and sexual reproduction, drawn from the provided lecture notes.

Meiosis

A special type of cell division used for sexual reproduction that reduces chromosome number from diploid to haploid.

Diploid (2n)

Cells containing two chromosomes of each type.

Haploid (n)

Cells containing a single set of chromosomes.

Homologous chromosomes

Pairs of chromosomes that are similar in shape, size, and genetic content, one inherited from each parent.

Karyotype

A display of chromosomes arranged by size, shape, and banding pattern.

Alleles

Different versions of a gene that exist at a particular locus on homologous chromosomes.

Synapsis

The pairing of homologous chromosomes during Prophase I of meiosis.

Bivalent (Tetrad)

A structure formed during synapsis that consists of two homologous chromosomes.

Crossing Over

The exchange of genetic material between nonsister chromatids during meiosis.

Independent Assortment

The random orientation of homologous chromosome pairs during metaphase I of meiosis.

Interkinesis

A short resting period between meiosis I and meiosis II where cells may briefly enter a resting state.

Centromere

The region of a chromosome where the two sister chromatids join.

Nondisjunction

The failure of homologous chromosomes or sister chromatids to separate properly during cell division.

Trisomy

A condition wherein an individual has three copies of a particular chromosome instead of the normal two.

Monosomy

A condition characterized by the presence of only one of a particular type of chromosome.

Euploidy

A condition with the correct number of chromosomes for a species.

Aneuploidy

A condition with an abnormal number of chromosomes, which can result from nondisjunction.

Spermatogenesis

The process of sperm cell development, which includes meiosis.

Oogenesis

The process of egg cell development, which also includes meiosis.

Zygote

The fertilized egg that forms when a sperm and egg unite.

Somatic cells

Any cells of the body except for germ cells; they contain the full set of chromosomes.

Fertilization

The process whereby a sperm and egg join to form a zygote.

Bivalent formation

The pairing of homologous chromosomes, previous to crossing over.

Genetic variability

The variety of genetic combinations resulting from sexual reproduction.

Traits

Characteristics that are inherited or influenced by genes.

Gametes

Haploid cells produced by meiosis that are involved in sexual reproduction.

Cytokinesis

The final step of cell division where the cytoplasm divides, forming two cells.

Mitosis

The process of cell division that creates genetically identical daughter cells.

Diploid Generation

The phase in a life cycle where organisms contain two sets of chromosomes.

Sister chromatids

Identical copies of a chromosome that are connected at the centromere.

Parental Generation

The generation from which offspring are derived.

Life Cycle

The series of changes in the life of an organism, including reproduction.

Turner Syndrome

A condition caused by the presence of a single X chromosome in females, leading to developmental issues.

Klinefelter Syndrome

A condition in which males have an extra X chromosome (47, XXY), leading to various physical abnormalities.

Poly-X Females

Females with more than two X chromosomes, sometimes referred to as “super females.”},{