Flashcards in Lecture #5 -- Reproductive Physiology Deck (62):
Functions of the Reproductive System
Produce Sex Hormones
Produce and Deliver Gametes
Chemical structure of protestin, corticoids?
Chemical structure of androgen?
Chemical structure of Estrogens?
Why doesn't the ovary make gluco and mineralo corticoids?
No 21- or 11- beta hydroxylases
Difference between delta 4 and delta 5 pathways?
Delta 4 -- 17-OH progesterone
Delta 5 -- DHEA
Where do the delta 4 and delta 5 pathways come back together
What is an estrogen?
A substance capable of producing the typical changes of estrus
What are the typical changes of estrus (3)
Enlargement of the uterus
Cornification of the vaginal epithelium
Mating behavior in immature females
Effect of estrogen on cervix?
Increase in quantity and decrease in viscosity of mucus
Effect of estrogens on vagina?
Effect of estrogen on bone?
Promotes linear growth and epiphyseal closure
Actions of progesterone?
1. Conversion of proliferative to secretory endometrium
2. Inhibition of smooth musc. contractility.
3. Natiuresis w/ elevated Resp. Rate
4. Increased Cervical mucus viscosity
5. breast growth
What converts testosterone to dihydrotestosterone?
5 alpha reductase
Different developmental roles of testosterone and DHT?
Test. -- Epid., Vas, Sem vesicle
DHT -- External Genetalia
DHT deficiency causes
How are androgens turns into estrogens?
Aromatase present in granulosa cells and adipose
Relationship of Sex Binding Globulin to....
Inversely related to weight, insulin, and androgens
Hormonally, what triggers the onset of puberty?
Decreasing sensitivity of hormonal feedback too
How is puberty repressed in early years?
CNS inhibits GnRH release
Very sensitive negative feedback
Normal age for Thelarche (breast dev)
Normal age for pubarche?
Normal age for Menarche
Its abnormal is women don't start puberty by...
Male puberty follows female by approx
Difference between precocious pseudopuberty and precocious puberty
Prec. PseudoPub -- Early 2dary sex char., no gametes
Prec. Pub -- Above, but w/ gametes
Relationship of teste to body temp
testes are 3 degrees cooler
Action of LH on testicle?
Activated Cholesterol Desmolase
Initiates Testosterone synthesis
Action of FSH on testicle?
Acts on Sertoli/Sustentacular cells
Stim synthesis of androgen binding proteins, spermatogenesis
GnRH pulese happen how frequently?
8-14 times per day
Role of Sertoli cells?
Provide nourishment to developing spermatozoa
Intercellular junctions fo BTB
Genetic difference between spermatogonium and spermatozoa?
Spermatogonium -- 2n
Where does spermiogenesis take place? How long does it take?
Membrane recesses of the Sertoli Cells in the seminiferous tubules
Enzyme present in acrosome for spermatozoa penetration of ovum
4 Jobs for the Epididymus
Energy source for spermatozoa?
Normal Sperm Count?
Problem Sperm Count?
Normal -- 40 - 100 million/mL
Not problematic till below 20 million/mL
Normal sperm motility?
Difference between Ejaculation, Emission, and Expulsion?
Ejac. -- Forceful ejection of sperm from the urethra
Emission -- Entry of ejacultory fluid into urethra
Expuls. -- Ejection of fluid from urethra and bulbo
Describe a primary follicle
Oocyte arrested in prophase of meiosis
Surrounded by a single later of granulosa cells
Influence of LH on egg
LH acts on theca cells
Use the delta-4 path to make androgens for the granulosa cells
Influence of FSH on egg?
FSH induces aromatase, leading to estrogen production
Cause of the LH surge.
Caused by positive feedback of estradiol on Ant P
Result of the LH surge?
Local prostaglandins and proteases weaken follicular wall
Resumption of Meiosis
What pathway becomes active in the Luteal phase? Why?
Production of Progesterone
Progesterone peaks at ____ days after ovulation
Luteal phase length =
Significance of HCG?
Homolog of LH
Maintains the Corpus Luteum in early pregnancy
How does oral contraception work?
Combination of estrogen and progesterone
Suppresses HPA, presenting the stimulation needed for endometrial development
Who makes inhibin? Why?
Produced by luteinized granulosa cells
- feedback on AP FSH release
What is the most sensitive marker of ovarian follicular reserve?
Describe the proliferative phase of the uterus
Rebuilding the endometrial layer following its previous shedding
Late phase -- thickened from grandular hyperplasia, stromal edema
Most important hormone of proliferative phase?
Describe the secretory phase of the uterus
Cessation of mitosis
Glandular secretions and tortuosity
Coiling of spiral arteries leads to ischemia
Two forces to get sperm to the endocervix
Female genital tract contractions
What happens in the acrosomal reaction?
Sperm releases hyaluronidase and other enzymes to break through zona pellucida
Inner acrosomal membrane fuses with it
Where does fertilization usually occur?
What is superfecundation?
Fertilization by two partners in one ovulatory cycle.
Four categories of causes of infertility
What might be throught of an an unexplained cause of infertility.
Hostile cervical mucus
What happens in polycystic ovarian syndrome
Ovulatory dysfunction with hyperandrogenism
High Androgens inhibit selection of dominant follicle