Physiology - basic science Flashcards
Cytotrophoblast
Implantation:
Inner trophoblastic layer with stem-cell activity
Placenta:
Inner layer of chorionic villi
Syncytiotrophoblast
Outer trophoblastic layer, SYNthesizes and secretes hormones (hCG)
Placenta:
Outer layer of chorionic villi
Theca cells: function and location
Follicular cell that responds to LH and synthesizes androstenedione from cholesterol via desmolase
Granulosa cells: function and location
Follicular cell that responds to FSH and converts androstenedione to estradiol via aromatase
Leydig cells: function and location
Secretes testosterone in response to LH
Located in testicular interstitium, homolog of theca cells
Sertoli cells: function? secretes what? location?
Secretes inhibin B, Anti-Mullerian Factor in male fetus, supports spermatogenesis
Located in seminiferous tubule lining
Inhibin B: secreted by what? function?
Secreted by granulosa cells / sertoli cells
Inhibits FSH
What is genetic imprinting?
Somatic cells have both maternally and paternally imprinted genes. During gametogenesis, all pre-existing epigenetic marks are stripped, and THEN:
- In females, maternally imprinted genes are marked again
- In males: paternally imprinted genes are marked again
5-alpha reductase: function
Converts testosterone to dihydrotestosterone (DHT)
Route of sperm
Spermatogenesis in seminiferous tubules»_space; rete testis (network of tubules)»_space; efferent ducts»_space; epididymis»_space; vas deferens»_space; joins seminal vesicle»_space; ejaculatory duct»_space; prostatic urethra»_space; membranous urethra»_space; penile urethra
What produces progesterone during pregnancy?
1st trimester: corpus luteum
2nd and 3rd trimesters: placenta
Human placental lactogen: function
Increases insulin resistance to increase extracellular glucose that fetus can take up
Estrogen potency ranking
Estradiol > estrONE (E1, menopause) > estriol (pregnancy)
