19.1 Reproductive systems

Question 1

testes

Answer 1

1. produce SPERM in the SEMINIFEROUS TUBULES (sustentacular cells/Sertoli cells), interspersed by testicular interstitium (INTERSTITIAL cells aka “LEYDIG cells” produces ANDROGEN)
2. secretion of sex hormones

Question 2

semen

Answer 2

nourishes the sperm

produced in the accessory glands:

1. prostate
2. bulbourethral glands - viscous mucous
3. seminal vesicles (60% total volume)

Question 3

parts of penis

Answer 3

two corpora cavernosa

one corpus spongiosum

Question 4

orgasm

Answer 4

stimulation by SNS

emission THEN ejaculation

emission = propulsion of sperm and semen into the urethra by contractions of smooth muscle

ejaculation = semen is propelled out of the urethra by rhythmic contractions of muscles at base on the penis

Question 5

CYTES = meiotic division

spermatogonia divide by MITOSIS (these are GERM CELLS)

Answer 5

spermatid (cell) -> spermatozoa (the sperm)

acrosome = head of sperm with hydrolytic enzymes required for penetration of ovum’s protective layer

bindin = protein on sperm surface attaches to receptors on the zona pellucida

Question 6

testosterone

Answer 6

stimulates division of spermatogonia

LH stimulates interstitial cells to secrete testosterone

FSH stimulates sustentacular cells

inhibin is secreted by sustentacular cells, which INHIBITS FSH release

Increased testosterone levels in blood decrease production of FSH

Question 7

development

Answer 7

early embryos have UNDIFFERENTIATED gonads, and posses both Wolffian ducts (internal male genitalia) and Mullerian ducts (internal female genitalia)

Mullerian is default in ABSENCE of testosterone

External genitalia are NOT derived from Mullerian ducts

Y chromosome leads to development of TESTES, releasing Mullerian inhibiting factor (MIF) and testosterone. MIF causes regression of mullerian ducts and prevents development of internal female genitalia. Testosterone leads to internal and external male genitalia

Question 8

Q514

Answer 8

Y chromosome results in Testes, that produce testosterone and MIF. MIF breaks down the Mullerian ducts, avoiding internal female genitalia. Missing testosterone receptors means no Wolffian ducts, meaning no internal male genitalia or external male genitalia. External genitalia defaults to female.