Reproductive System Flashcards
How long does it take to produce mature sperm?
21 days (complete turnover every 60d)
3 differences between spermatogenesis and oogenesis
- timing of mitosis: f- prior to birth/ m-after puberty
- f: 1 oocyte–> 1 mature ovum, 3 polar bodies // m: primary spermatocyte–> 4 spermatozoa
- f: 2nd meiotic division after fertilization
What is produced by seminal vesicles? prostate? role of each component???
- s.v.- fructose, citric acid, nutrients, (nourish), prostaglandins (motility), fibrinogen (clot)
- prostate- calcium, citrate, clotting enzyme, alkaline fluid (neutralization)
Sperm count considered infertile
Role of acrosome, cortical granules
- acrosome- enzymes in sperm head help penetrate wall of ovum
- cortical granules- in egg, inactivate receptors once sperm enters to prevent polyspermy
Mullerian vs Wolffian ducts
At what point in utero is sex determined?
8 weeks (2nd month) testosterone expressed or not - Mullerian ducts turn into female, wolffian ducts turn into male, we start with both
DHT is? Roles?
DHT= potent derivative of testosterone
- fetal development of male reproductive system
- pubertal growth of scrotum, prostate, hair, sebaceous glands
- prostatic secretion
Function of: testes epididymis/ductus deferens seminal vesicles prostate gland bulbourethral glands
- testes- produce sperm, testosterone
- epi/dd- sperm storage/maturation
- sv- bulk of semen-fructose, prostaglandins, clotting
- prostate- alkaline, clotting
- bulbourethral- mucus
Males- targets of GnRH, LH, FSH
GnRH- hypothalamus to ant pituitary, release LH/FSH
- LH–> leydig cells –> testosterone
- FSH–> sertoli cells –> spermatogenesis and inhibin for negative feedback on hypothalamus
ADT and prostate cancer
Androgen Deprivation Therapy- testosterone nourishes cancer cells, ADT–> lose bone density, muscle mass
- Prostate cancer- late 60s/early 70s, predisposed if obese, sedentary, poor dietary habits
- Higher incidence in caucasians, higher mortality in african americans
Andropause
late in life, gradual
testosterone down –> decreased libido, strength, bone density, body mass
protein synthesis, CV function
Arteriosclerosis effects on male reproductive
can cause erectile dysfunction, blocks small vessels around penis
Ovarian cycle (days)
- Follicular phase- 15 d on avg (9-23)
- Ovulatory phase- 1-3 d, ends w ovulation
- Luteal phase- 13 d
Endometrial cycle
AKA thickness of endometrium
- proliferative phase (11 d, thickens, ovaries produce estrogen)
- secretory phases (12 d, thickened, CL makes progesterone)
- Menstrual phase (5 d, low E+P)
Atresia
6-12 follicles start to mature each month due to FSH, atresia = breakdown of all but 1
Role of corpus luteum
- depends on LH (lutenizing homone)
- Follicle after ovulation, provides estrogen & progesterone to implant blastocyst, maintain zygote until placenta grown
- degenerates in 14 d (inhibin) if no fertilization
Functions of estradiol (estrogens)
- pubertal growth
- fat deposition
- increase vascularization of skin
- inhibits osteoclasts
Functions of progesterone
- secretory changes in uterus
- breast development
Perimenopause v menopause
- perimenopause- changes in menstrual cycle, body temp up, sleep disturbances, anxiety, depression
- menopause- early 50s, hot flashes, night sweats, insomnia, low libido, headaches, mood swings, vaginal dryness, bone loss
Why use/not use hormone therapy?
Negative side effects- cancer, heart disease
- prescribed for maximum of 5 yrs if severe symptoms of menopause
hCG (human chorionic gonadotropin)
- produced 8-9 d after fertilization
- maintains corpus luteum, stimulates P + E production by CL
- stimulates testosterone production in male fetus
- hCG receptors in endometrium can inhibit contractions produced by oxytocin
Function of estrogens during pregnancy
- estradiol produced by CL for 1st 5-6 wk stimulated by hCG, then placenta
- increases uterine blood flow, stimulates growth of myometrium
- growth (w progesterone) of ductal breast tissue
- (w relaxin) softens pelvic ligaments
Parturition - 4 phases
Parturition = labor
0: conception to start of labor
1: …to delivery of fetus
2: …to delivery of placenta
3: postpartum, involution of uterus
Positive feedback theory of parturition
Cervical stretch by baby’s head excites fundic (uterine) contraction, et cetera
