Essentials of Genetics - Chapter 5: Sex Determination and Sex Chromosomes

This set of flashcards covers key concepts related to sex determination and sex chromosomes as discussed in Chapter 5 of Essentials of Genetics. The flashcards address major findings about chromosomes, conditions linked to genetic configurations, and mechanisms of sex determination.

What chromosomes are primarily linked to sex determination in humans?

X and Y chromosomes.

What is the karyotype of females and males?

Females have XX, while males have XY.

What does the Y chromosome determine in humans?

The Y chromosome determines maleness.

What condition is associated with the presence of an extra X chromosome in males (47,XXY)?

Klinefelter syndrome.

What chromosome configuration is seen in Turner syndrome?

45,X (a single X chromosome).

How does dosage compensation occur in females?

It involves the inactivation of one X chromosome to balance gene expression with males.

What is a Barr Body?

An inactive X chromosome that is highly condensed and lies against the nuclear envelope.

What is the Lyon Hypothesis?

The hypothesis that X inactivation is random, resulting in all descendant cells having the same inactivation pattern.

How is sex determined in Drosophila?

By the ratio of X chromosomes to sets of autosomes.

What is temperature-dependent sex determination (TSD)?

A mechanism where the environment, particularly temperature, influences the sex of offspring in some reptile species.