Quiz 3 Flashcards
Sex differentation
Subsequent events that ultimately produce either the male or female sexual phenotype. In other words, the process of becoming female or male
Barr body
Females must have 1 deactivated X or else problems occur
X-inactive specific transcript (XIST)
A product of an X-linked gene that is necessary and sufficient to inactivate 1 X chromosome
First rule of sex determination
Development of gonads into testis of ovary determines the sexual differentiation of embryo
Second rule of sex determination
Y chromosome carried sex determining information in mammals
3 levels of sexual dimorphism
- Genetic sex: XX or XY
- Gonadal sex: testes of ovaries
- Phenotypic male or female
Testis determining factor (TDF)
Acts on undifferentiated gonads to create testis
Supporting cells
Sertoli cells in males and follicle cells in females
Steroidal cells
Produce gonadal hormones. Leydig cells in males and thecal cells in females
Connective tissue cells
Form structural framework of go ad
Primary sex differentation
Mammalian sex determination is controlled by SRY gene. SRY expression induces testes, lack of SRY results in ovaries
Secondary sex differentation
all hormonally controlled sex development beginning at embryogenesis. Behavior and outside characteristics
Anti-mullerian hormone (AMH)
Causes Müllerian ducts to regress
Testosterone
Virilization of wolffian ducts to form outside penis
Synthesis of sec hormones
Leydig cells produce testosterone
Thecal/granulosa produce estrogen
Adrenal glands also produce
External genitalia in males
Testosterone, 5 alpha-reductase, DHT, male outside
Congenital adrenal hyperplasia (CAH)
Enlarged adrenals and lack of enzyme to produce cortisol from adrenal cortex
Masculinization of brain
Testosterone, aromatase, estrogen, male brain
Sex determination
Initial event that determines whether the gonads will develop as testes or ovaries
