Fertilization etc Flashcards Preview

Q3 Physio II Final > Fertilization etc > Flashcards

Flashcards in Fertilization etc Deck (30):
1

Pregnancy Stage 1?

Fertilization: methods of assisting sperm

Contractions of myometrium/oviduct sm mm move sperm,
Allurin attracts sperm to egg in ampulla,
Cervical mucous thins/↑ pH

2

Sperm Capacitation is?

Initiated thru tract:
Cholesterol w/draw from head,
Surface proteins redistrib,
Ca2+ influx ↑ motility

3

Sperm route thru follicle?

Corona radiata -> zone pellucida -> ovum cyto

4

Acrosomal Rxn is?

Sperm receptors bind ZP3 in zona pellucida ->
acrosin released from sperm ->
allows entry into zona

5

Zona Reaction is?

sperm fertilin binds ovum integrin receptor ->
Zona degrades ZP3 receptors/harden zona -> prevents polyspermy

6

Pregnancy Stage 2?

Implantation:
Fertilized ovum -> blastocyst -> luteum

7

Blastocyst made of what type cells? (2)

1) Trophoblasts (form w/ endometrium to make placenta)

2) Inner cell mass (become embryo)

8

Blastocyst implants endomet how?

enzymes make hole for implant ->
nutrients released for embryo

9

Progesterone role in implantation?

∆ uterus to secretory gland ->
glycogen/lipds

Relaxes myometrium

Days 20-24 optimal

10

Pregnancy Step 3?

hCG secretion

11

hCG is?

Released when?

Human Chorionic Gonadotropin:
Hormone from placenta -> maintains corpus luteum -> stim luteum secretion of prog/est until placenta takes over

Secreted days 8-11 of conception

12

Fxn of placenta?

1) digestive, respiration, renal for fetus
2) prevents immun rejection
3) endocrine hormone secretion (hCG, est, prog)

13

Estrogen in pregnancy?

Estriol most important
Levels ↑↑
Requires fetus and placenta for synth
Urine estrogen marker for fetal health

14

Estrogen role during pregnancy?

↑ myometrium growth for labor
↑ breast ducts
Stim prolactin release
Softens pelvic ligaments
Inhib lactation

15

Progesterone in pregnancy?

Levels ↑
wks 6-12 from luteum
wk 13 on from placenta
Synth requires maternal cholesterol

16

Progesterone role in pregnancy?

∆ uterus to secretory gland
cervical plug
inhib contractions
inhib PG synth
inhib lactose synth

17

Gestation Stage 2?

38 wks
maternal physical ∆s support pregnancy

↑ blood vol, CO, resp, excretion, etc

18

Uterine ∆ for 2rd trimester?

Prog ↓ -> uterus more excitable
Cervix relaxes via Relaxin from luteum/placenta

19

Gestation Stage 3?

Parturition (labor/delivery/birth)

20

Labor and estrogen?

↑ estrogen:

1) links cells for coordinated contractions
2) ↑ myo response to oxytocin
3) ↑ PGs for cervical ripening

21

Labor and Oxytocin?

Stored in post pituitary,
Circulating levels don't rise but myo oxytocin receptors ↑↑

22

Labor and Corticotrophin-Releasing Hormone (CRH)?

Preps fetus to live:
Fetal CRH ↑ -> ↑ fetal ACTH -> ↑ fetal DHEA ->
↑ conversion into estrogen in placenta

fetal ACTH also ↑ cortisol -> matures lungs

CRH in maternal placenta is "clock"
↑ CRH -> early delivery
↓ CRH -> late delivery

23

Labor and Inflammation?

Uterine stretch and macrophages from ↑ pulmonary surfactants activate NF-kB in uterus

NF-kB stim inflamm cytokines/PGs ->
↑ cervical softening
--------

Bacteria, allergic rxn, multiples can trigger labor

24

Labor positive feedback?

pressure of fetus ↑ oxytocin

25

Stages of labor? (3)

1) cervical dilation
2) delivery of baby
3) delivery of placenta

26

Gestation Stage 4?

Lactation:
Prolactin stims alveolar
W/draw of placental steroids stim lactation

27

Prolactin?

Lactogenesis hormone
Synth'd by pituitary
Release stim by Thyrotropin-releasing hormone
Release inhib by Dopamine

28

Prolactin block ovulation how?

(Lasts for 7 months)
Inhib GnRH release -> inhib LH/FSH
Antagonizes action of LH/FSH on ovaries

29

Milk Lactoferrin does?

blocks growth of harmful bacteria in milk

30

Milk Bifidus Factor does?

promotes growth of helpful bacteria