Final: Male Repro Flashcards
What is the progression of spermatogenesis?
Primordial germ cells –> spermatogonia –> primary Spermatocytes –> Secondary spermatocytes —> Spermatids —–> mature sperm
Where are sertoli cells located?
within seminiferous tubules.
_____ _______ act as nurse cells (sustentacular cells) that surround primary spermatocytes and get them through the process of spermatogenesis and spermiogenesis.
Nurse cells
What is spermiogenesis
differentiation of spermatids into mature sperm
What is spermiogenesis
differentiation of spermatids into mature sperm
What forms the acrosome
proacrosomal nesicles coalesce
what does the acrosome contain?
hyaluronidase and proteolytic enzymes
What does the acrosome cap?
the nucleus
What happens to the centrioles during spermiogenesis
they migrate to the side of nucleus opposite acrosome.
In spermigenesis what organize the flagellum
distal centriole
where do mitochondria locate in spermiogenesis
move to base of forming flagellum and wrap around it.
What is the residual body in spermiogenesis
excess cytoplasm is sloughed off
Where are sperm cells stored until ejaculation?
epididymis
how long does passage through the epididymis take?
several days
Where are the cells of leydig found?
interstitial spaces in testes
what do the cells of leydig secrete?
testosterone
what do the cells of leydig secrete?
testosterone
What stimulates the secretion of testosterone in the cells of leydig?
luteinizing hormone secreted by anterior pituitary-
-FSH is also necessary for spermatogenesis
Where are the seminal vesicles located?
paired, behind prostate.
What is the structure of the seminal vesicles?
a loculated tube lined with secretory epithelium
What does the mucoid material secreted by seminal vesicles contain?
Fructose citric acid additional nutrients prostaglandins fibrinogen
during emission and ejaculation contents of seminal vesicles are emptied into?
ejaculatory ducts containing sperm.
during emission and ejaculation contents of seminal vesicles are emptied into?
ejaculatory ducts containing sperm.
during emission and ejaculation contents of seminal vesicles are emptied into?
ejaculatory ducts containing sperm.
what percentage of semen is from seminal vesicles?
60% of total volume
What is the role of fructose for sperm
energy production
___________ make cervical mucous more receptive to sperm movement and may cause retro-peristaltic contractions of uterus and fallopian tubes.
Prostaglandins
What percentage of the semen volume is from the prostate gland?
30% of total volume
What does the prostate gland secrete?
a milky fluid containing calcium, citrate ions phosphate ions, clotting factor, and profibrinolysin
How can the prostate gland fluid help to neutralize acidity of other seminal fluids and vaginal secretions of the female?
it is slightly alkaline
Define Androgens
any steroid hormone that has masculinizing effects
What are 3 androgens
testosterone
dihydrotestosterone
androstenedione
Androgens can be synthesized in testes and adrenal glands from what?
cholesterol and Acetyl-CoA
When is testosterone almost nonexistent
during childhood, between newborn and adult
97% of testosterone is loosely bound with ________ or tightly bound with ______ _______
albumin, beta globulin
how long does testosterone circulate in the blood?
30 minutes to several hours
what are the fates of testosterone?
transferred to tissues or degraded to inactive product that are subsequently secreted.
Testosterone that enters tissues mostly converted to ________, especially in prostate and in fetal external genitalia
dihydrotestosterone
What is non-fixed testosterone converted to? where does this occur
androsterone and dehydroepiandrosterone in the liver
What is non-fixed testosterone converted to? where does this occur
androsterone and dehydroepiandrosterone in the liver
after conversion of testosterone in the liver, what can it be conjugated to? how is it secreted?
conjugated as either glucuronides or sulfates. Excreted into gut via bile or urine via kidneys
What hormone can increase reabsorption of sodium in distal kidney tubules?
testosterone
Where does testosterone come from in females?
adrenal glands
Where does testosterone come from in females?
adrenal glands
what is produced by neurons located in arcuate nuclei of hypothalamus?
Gonadotropin-releasing hormone (AKA LH releasing hormone)
a 10-AA peptide
how is gonadotropin releasing hormone transported to the anterior pituitary
hypothalamic-hypophyseal system.
What does gonadoptropin releasing hormone stimulate?
the anterior pituitary to produce LH and FSH
What is a glycoprotein that activates cAMP second messenger system in target tissue?
Luteinizing hormone (LH)
What causes leydig cells to secrete testosterone?
Luteinizing Hormone
What effect does testosterone have on hypothalamus
a negative feedback effect.
what is secreted by sertoli cells that inhibits secretion of FSH by anterior pituitary?
inhibin
-can also inhibit secretion of GnRH to a lesser extent
