Male Reproductive Physiology (Lec 20) Flashcards
In regards to spermatogenesis, pimordial germ cells migrate into future testes and become ____
spermatogonia
In regards to spermatogenesis, spermatogonia begin mitotic division at puberty and become ___ ___
primary spermatocytes
In regards to spermatogenesis, primary spermatocytes complete the first half of meiosis and become ___ ___
secondary spermatocytes
In regards to spermatogenesis, secondary spermatocytes complete the second half of meiosis and become ____
spermatids
In regards to spermatogenesis, spermatids undergo differentation to become ___
sperm
Where are Sertoli cells located?
within the seminiferous tubules
____ cells act as nurse cells that surround primary spermatocytes and “nurse” them through the process of spermatogenesis and spermatogenesis
Sertoli
Sertoli cells form estrogens from what?
testosterone
note: thought to be important for spermiogenesis
In regards to spermiogenesis, roacrosomal vesicles coalesce to form ____ which contains hyaluronidase and proteolytic enzymes
acrosome
In regards to spermiogenesis, the acrosome caps what?
nucleus
In regards to spermiogenesis, ____ migrate to side of nucleus opposite of acrosome
centrioles
In regards to spermiogenesis, distal centriole begins to organize ____
flagellum
In regards to spermiogenesis, mitochondria move to base of forming flagellum and do what?
wrap around it
In regards to spermiogenesis, what happens to excess cytoplasm?
it sloughs off and forms residual body
In regards to spermiogenesis, sperm cells are stored in ___ until ejaculated
epididymis
In regards to spermiogenesis, sperm cells must remain in epididymis for a minimum of ___ to ___ hours in order to gain motility
18 - 24
In regards to spermiogenesis, passage through the epididymis takes how long?
several days
Name the following cell:
found in interstitial spaces in testes; secrete testosterone; stimulated by luteinizing hormone secreted by AP
cells of leydig
Each seminal vesicle is a located tube lined with what?
secretory epithelium
Seminal vesicles secrete a mucoid material that contains what?
fructose, citric acid, additional nutrients, prostaglandins, fibrinogen
During emission and ejaculation, the contents of seminal vesicles are emptied into ejaculatory ducts containing what? What percentage of total volume of the semen?
sperm; 60%
Fructose provides energy for sperm. True or false?
true
____ make cervical mucous more receptive to sperm movement and may cause retro-peristaltic contractions of uterus and fallopian tubes
prostaglandins
The prostate gland is responsible for what percentage of the total amount of semen?
30%
Describe the fluid produced by the prostate gland
milky; contains calcium, citrate ions, phosphate ions, clotting enzyme, and profibrinolysin
True or false?
The prostate gland produces slightly acidic fluid
false; alkaline
note: may help to neutralize acidity of other seminal fluids
Any steroid hormone that has masculinizing effects is considered an ___
androgen
Testosterone, dihydrotestosterone, and androstenedione are all considered what?
androgens
Where are androgens synthesized and what are the synthesized from?
testes & adrenal glands; cholesterol & acetyl-coA
Testosterone is formed by interstitial cells of ___
leydig
Testosterone is formed by interstitial cells of ___
leydig
After secretion, 97% of testosterone is loosely bound with ___ or tightly bound with __ ___
albumin; beta globulin
Testosterone, after secretion, circulates in blood for how long?
30 min to several hours
Testosterone that enters tissues is mostly converted to ____, especially in prostate and in fetal external genitalia
dihyrotestosterone
Testosterone that is not fixed in tissues is converted in liver to what?
androsterone and dehydroepiandrosterone
Testosterone that is not fixed in tissues is conjugated as either ___ or ___
glucoronides or sulfates
Testosterone that is not fixed in tissues is excreted into gut via __ or ___ via kidneys
bile or urine
True or false? One of the functions of testosterone is responsible for male hair pattern growth
true
note: associated with baldness
Testosterone is responsible for hypertrophy of ___
larynx
Testosterone is responsible for increased skin ___ and secretion rate of ___ glands
thickness; sebaceous
Testosterone is responsible for increased BMR and hematocrit. True or false?
true
Testosterone ___ reabsorption of sodium in distal kidney tubules
increases
Testosterone ___ reabsorption of sodium in distal kidney tubules
increases
Gonadotropin-releasing hormone is produced by neurons located in ___ nuclei of the hypothalamus
arcuate
Gonadotropin-releasing hormone is transported to AP via what system?
hypothalamic-hypophyseal
Gonadotropin-releasing hormone stimulates AP to produce __ and __
LH and FSH
LH is a glycoprotein that activates cAMP second messenger system in target tissue. True or false?
true
LH causes ___ cells to secrete testosterone
leydig
note: testosterone has negative feedback effect on hypothalamus
Inhibin is secreted by ___ cells
Sertoli
Inhibin inhibits secretion of __ by AP
FSH
