Sex Determination and Sex-Linked Characteristics

These flashcards cover key concepts related to sex determination, sex-linked characteristics, and genetic inheritance mechanisms.

Sex determination

The mechanism by which sex is established in an organism.

Gametes

Haploid cells that fuse during fertilization to form a diploid zygote.

Diploid (2n)

Cells that contain two sets of chromosomes.

Haploid (1n)

Cells that contain a single set of chromosomes, such as gametes.

Autosomal inheritance

Transmission of traits carried on autosomes, chromosomes found in both males and females.

Sex-linked inheritance

Transmission of traits or genes carried on the sex chromosomes.

Chromosomal sex determination

System of determining sex based on the combination of sex chromosomes.

XX-XY system

A chromosomal system where XX produces females and XY produces males.

SRY gene

The male-determining gene located on the Y chromosome.

Androgen-insensitivity syndrome

A condition where XY individuals have female external characteristics but do not develop female reproductive organs due to defective androgen receptors.

Barr bodies

Inactivated X chromosomes in female cells, resulting from random X-inactivation.

Poly-X females

Individuals with more than two X chromosomes who are often taller and thinner.

Klinefelter Syndrome

A genetic condition in males characterized by an extra X chromosome (XXY), leading to small testes and reduced secondary sexual characteristics.

Turner Syndrome

A chromosomal condition in females characterized by the presence of only one X chromosome (XO), often resulting in underdeveloped secondary sex characteristics.

X-inactivation

A process that equalizes gene dosage between males (XY) and females (XX) by randomly inactivating one X chromosome in females.

Linkage

The tendency of genes located close to each other on a chromosome to be inherited together.

Morgan's flies

Refers to Thomas Hunt Morgan's experiments with Drosophila that contributed to the understanding of genetic linkage and sex determination.

XY system

A chromosomal system in which males carry XY and females carry XX.

Pseudoautosomal region

Region on the sex chromosomes where X and Y chromosomes pair during meiosis.

X-linked trait

A trait associated with a gene found on the X chromosome.