reproductive Flashcards
testes: location `
outside of the body for optimal spermatogenesis temperature
testes: endocrine function
interstitial cells of leydig produce testosterone
testes: exocrine function
seminiferous tubules produce sperm
path from seminiferous tubules to ductus deferens
seminiferous tubules –> tubulus rectus –> rete testis –> efferent ductules –> ductus deferens
tunica albuginea: male
- inner covering of testes, made of dense irregular CT
- thickens posteriorly to form mediastinum testis
tunica vaginalis: male
- outer mesothelium of testes
seminiferous tubules: tunica propria
peritubular tissue with myoid cells, which make peristaltic waves to move sperm and testicular fluid
spermatogonia: location, characteristics
- adjacent to basement membrane
- undifferentiated male germ cells that undergo mitotic division
primary spermatocytes: location, characteristics
- occupy middle 1/3 of germinal epithelium
- diploid w/ 46 chromosomes, 92 chromatids
- undergo reductional division to produce secondary spermatocytes
secondary spermatocytes: characteristics
- haploid with 23 chromosomes and 46 chromatids
- undergo second meiotic division (equational, separating sister chromatids) to produce spermatids
spermatids: location, characteristics
- at luminal surface
- one secondary spermatocyte produces 2 spermatids w/ 23 chromosomes and 23 chromatids
spermeogenesis: golgi phase
- acrosomal vesicle w/ hydrolytic enzymes + centrioles begin forming flagellum
spermeogenesis: cap phase
- acrosomal vesicle binds and spreads over nuclear envelope, forming acrosomal cap
spermeogenesis: acrosome phase
- nucleus condenses, flattens, elongates
- cytoplasm is displaced
- mitochondria form sheath around flagellum
spermeogenesis: maturation phase
sertoli cells remove excess cytoplasm, sperm released into lumen
ovarian cycle: theca cell in follicular phase
- LH binding
- synthesis of androtenedione from cholesterol –> pregnenolone –> progesterone
ovarian cycle: granulosa cell in follicular phase
- FSH binding induces production of aromatase, LHRs on granulosa cells
- aromatase converts androstenedione to estradiol
ovarian cycle: theca-lutein cells
- continue to produce androstenedione from cholesterol
ovarian cycle: granulosa-lutein cells
- continue to produce estrogens from androgens
- LH now stimulates production of progesterone from cholesterol
menstrual cycle: menses hormones
- estrogen and inhibin: - feedback on FSH
menstrual cycle: proliferative phase
- follicle is selected
- LH surge begins right before ovulation
- estrogen is high: + feedback on LH, some FSH
sertoli cells
- columnar, extend from basement membrane to lumen of seminiferous tubules by spermatogenic cells being embedded along sides, luminal surface
- form blood-testis barrier
- secrete androgen binding hormone, inhibin: both stimulated by FSH
leydig cells: location, function
- loose CT between seminiferous tubules
- secrete testosterone
ductus deferens: structure
- pseudostratified epithelium w/ stereocilia
- 3 muscle layers
seminal vesicles: structure
- convoluted pseudostratified –> simple columnar epithelium
- smooth muscle inner circular, outer longitudinal
- columnar cells secrete seminal fluid: 70% of ejaculate
penile urethra: epithelium
pseudostratified columnar –> stratified squamous at glands
ovary: epithelium
- outer covering: germinal epithelium
- tunica albuginea of dense irregular CT
primordial follicle: structure
- primary oocyte arrested in prophase 1, surrounded by single layer of follicular cells
primary follicles: structure
- follicular cells –> stratified (become granulosa cells)
- zona pellucida
- theca interna: steroid producing
- theca externa: outer collagen, smooth muscle
secondary follicles: structure
- antrum formation w/ hyaluronic acid
- cumulus oophorus w/ corona radiata forms
ovulation: formation of first polar body
- after first meiotic division, along w/ production of secondary oocyte
ovulated product
secondary oocyte, zona pellucida, corona radiata
oviduct: structure
- simple columnar mucosa
- inner circular, outer longitudinal muscle
- mesosalpinx continuous w/ broad ligament
fertilization: steps
- ovulated product moves to ampulla
- sperm undergo capacitation
- penetrate zona pelludica –> cortical rxn prevents polyspermy
- sperm enters secondary oocyte, forms male pronuc
- second meiotic division
uterus during menstruation
- ischemic functional layer degenerates
uterus during proliferation
- estrogen influences functional layer rebuilding from basal layer
uterus during secretory phase
- estrogen, progesterone influence
- endometrium thickness, glands fill w/ fluid
- corpus luteum looks for hGC
uterus during ischemic phase
- basal arteries constrict
- endometrium becomes pale, shrinks
FSH in females, males
- females: follicle growth
- males: spermatogenesis
LH in females, males
- females: corpus luteum formation
- males: testosterone production
estrogen functions
- sensitization of follicles to LH, FSH, uterus to oxytocin
progesterone functions
- endometrium from proliferative –> secretory
leydig cell: sex steroid synthesis
- cholesterol converted to testosterone, stimulated by LH
sertoli cell: sex steroid synthesis
- testosterone enters from leydig –> converted to estradiol by aromatase
- secretes ABP
- FSH stimulation
males: parasympathetic
- erection by vasodilatory action on penile arterioles
- NO release, increases intracellular cGMP —> smooth muscle relaxation
- PDE5 breaks down cGMP: vasoconstriction –> flaccidity
males: sympathetic
- release of seminal fluid into prostatic urethra, spinal reflex arc w/ smooth, skeletal muscle –> ejaculation
hCG
- secreted by blastocyst
- binds LH on corpus luteum, preventing degradation
maternal-placental-fetal axis: progesterone
- can be produced without fetus
maternal-placental-fetal axis: estrogen
- needs fetal adrenal gland synthesis of DHEAS –> 16-OH DHEAS in fetal liver
let down reflex
- PRL release
- oxytocin –> milk ejection
