Sexual Differentiation + Male Reproductive System Flashcards
What are the three levels of sexual dimorphism?
Genetic Sex: XY (male), XX (female)
Gonadal Sex: Testes (male), Ovaries (female)
Phenotypic Sex: External genitalia, Secondary sex characteristics
What is the role of the SRY gene in sex determination?
The SRY gene on the Y chromosome encodes the Testis Determining Factor (TDF), which triggers testis differentiation, leading to the formation of Sertoli and Leydig cells and the production of male sex hormones.
What are the main genetic sex disorders?
Turner Syndrome (X0): Female with low IQ, infertility, and short stature.
Klinefelter Syndrome (XXY): Male with low IQ, infertility, and taller stature.
Androgen Insensitivity Syndrome (AIS): XY individuals with female phenotype due to lack of androgen receptors.
What are the main components of the male reproductive system?
Gonads: Testes (spermatogenesis and hormone production)
Reproductive Tract: Epididymis, vas deferens
Accessory Glands: Prostate, seminal vesicles, bulbourethral glands
Describe the Hypothalamic-Pituitary-Gonadal Axis in males.
Hypothalamus: Releases GnRH
Pituitary: Releases LH (stimulates Leydig cells) and FSH (stimulates Sertoli cells)
Testes: Leydig cells produce testosterone; Sertoli cells support spermatogenesis.
What is the difference between testosterone and DHT?
DHT (Dihydrotestosterone) is a more potent androgen converted from testosterone by 5α-Reductase, crucial for the development of male external genitalia and secondary sexual characteristics.
What are the stages of spermatogenesis?
Proliferation: Spermatogonia divide by mitosis.
Growth: Primary spermatocytes undergo meiosis I.
Maturation: Spermatids undergo meiosis II and differentiate into mature spermatozoa.
What are the functions of testosterone in males?
Development of internal male genitalia
Support of spermatogenesis
Development of secondary sexual characteristics
Promotion of libido/ sex drive
Muscle growth and protein synthesis
How does the male and female genitalia develop?
What are plasma testosterone converted to?
What are the 3 stages of spermatogenesis
What are the difference between mitosis and meiosis
What happens during 5 alpha-reductase deficiency
What happens during Androgen insensitivity syndrome?
What is the comparison between 5 alpha- Reductase deficiency and AIS
