Flashcards in Lect 2: Male Repro Deck (11)
Full development and function of the seminiferous tubules require
androgens and FSH
In human males testosterone is produced mainly by
Nitrous oxide synthase contributes to erection by
activating soluble guanylate cyclases to increase cGMP levels that relax smooth muscle and increase blood flow
Testosterone is produced
in Leydig cells from cholesterol and pregnenalone precursors
The pubertal growth spurt is stimulated by the hormone
The hormone inhibin has direct negative feedback effects on the release of
a 16 y/o girl suffers from 5alpha-reductase deficiency. The individual was raised as a male but at puberty secondary sex characteristics and male growth occurred. Levels of which steroid is reduced during puberty?
A 55 y/o man complains of reduced libido and muscle strength. Serum analysis showed reduced levels of testosterone. Reduced activity in which hormone--target axis is causing the symptoms?
Leuteinizing hormone (LH)--Leydig cell
In order for male differentiation to occur during development testosterone must be secreted from the testes. WHich hormone stimulates the secretion of testosterone?
Human chorionic gonadotropin also binds to luteinizing hormone receptors on the interstitial cells of the testes of the male fetus, resulting in the production of testosterone in male fetuses up to the time of birth. This small secretion or testosterone is what causes the fetus to develop male sex organs instead of female sex organs.
A man is taking lots of med, one of which is interfering with the emission phase of sex. Which med is causing this?
inhibitor of sympathetic nervous system receptor
Emission is elicited by reflexes mediated by the sympathetic nervous system. Beta adrenergic antagonists interfere with the reflex. None of the other choices is involved.