12 reproduction Flashcards
testis
each consists of seminiferous tubules for production of sperm and
(Leydig cells)
sertoli cells; testis contained in scrotum- provides external cavity about 2deg
C lower
than body temp for sperm production.
Leydig cells
produces male sex hormones (testosterone + androgens) secreted in the presence of LH;
sertoli cells
stimulated by FSH surround and nurture sperm (also secrete peptide hormone inhibin, acts on the AP to inhibit FSH release)
- provide nourishment “nursing” to spermatids as they differentiate
into mature spermatozoa (sperm). They complete maturation (gain motility and are stored) in the
epididymis.
when do leydig cells secrete testosterone
beginning at
puberty
Epididymis:
coiled tube, one attached to each testis; site for final maturation and storage of
sperm.
Vas deferens:
transfer sperms from one epididymis to urethra.
Seminal vesicles:
Two glands, during ejaculation secrete into vas deferens: provide mucus
(liquid for sperm), fructose (energy for sperm), and prostaglandins (stimulate uterine contractions that
help sperm move into uterus).
Prostate gland:
secretes milky alkaline fluid into urethra; neutralizes acidity of urine that may
still be in urethra, also vagina acidity. Also neutralizes seminal fluid (too acidic from metabolic waste of
sperm)
Bulbourethral glands (aka Cowper’s):
secrete small amount of thick mucus of unknown function into urethra.
Penis:
transport semen (fluid containing sperm and secretions) into vagina.
Sperm:
see notes for more info
PLZ SEE REPRODUCTION VID NOTES
yes
path of sperm
SEVEnUP: seminiferous tubules
epidydmis
vas deferens
ejaculatory duct
urethra
penis -
pause before the V for maturation!
oogenesis
before birth
- oogonia (fetal cells)
(mitosis) primary oocytes
(meiosis) and remain at Prophase I until puberty (one primary oocyte during each menstrual cycle-28days, stim’d by FSH) continue its development through remainder of meiosis I within follicle (encircling cells that protect and nourish oocyte)
(completion of Meiosis I) secondary oocyte (most of cytoplasm) + polar body (small cytoplasm; may or may not divide but products
disintegrate) formed; secondary oocyte arrested at metaphase of meiosis II until
ovulation
ovulation
secondary oocyte from vesicular follicle (caused by LH surge). If fertilized by
sperm
(finishes meiosis II) ovum/egg (diploid once completely fertilized) + polar body (degenerate)
At puberty, FSH stimulates the growth of granulosa cells around the primary oocyte, which release a
viscious substance (zona pellucida). The structure at this stage is a primary follicle. Next theca cells
differentiate from the interstitial tissue and grow around the follicle to form a secondary follicle. Upon
stimulation by LH, theca cells secret androgen which is converted to estradiol (a type of estrogen) by the
granulosa cells in the presence of FSH and secreted into the blood. Typically estradiol inihibits LH
secretion by AP, but just before ovulation, estradiol levels rise rapidly, causing dramatic increase in LH
secretion.
secondary oocyte goes where
briefly located in the body cavity prior to enter the oviduct.
spermatogenesis
- puberty
- Spermatogonia cells
(mitosis) primary spermatocytes
(meiosis) 2 secondary spermatocytes
(meiosis II) 4 spermatids.
Semen
the combination of spermatozoa and the fluids that leave the penis upon ejaculation
Capacitation
allows egg penetration by sperm. final maturation of sperm. changes in sperm intracellular ion cxn, motility, and metabolism
eggs release what?
progesterone which aids in sperm motility and increases the likelihood of
fertilization.
menstrual cycle
proliferative, secretory and menstruation phases (lining shed)
SEE BIO BOOK
for menstrual