Pregnancy Flashcards
As the sperm is deposited into the vagina, before fertilizing the egg?
Sperm undergoes capacitation, which is rapid maturation helping the sperm swim rapidly in the female reproductive system
Capacitation involves the following:
1. glycoprotein is removed
2. intracellular changes
3. develop strong whip-like motion
From the female side, what aids in the movement of the sperm
uterine contraction
Where does fertilization occur? does fertilization always happen rapidly or can it occur over a couple of days
fertilization occurs in the fallopian tube and if there is an egg already there the sperm can fuse to it, however the sperm can stay in the fallopian tube for uptown 4 days upon arrival of egg
What chemical guides the sperm to the egg
chemotaxis
acromsomal enzymes
enzymes on the sperm that will remove layers of the head to allow the sperm head to penetrate the oocyte and release genetic material
What happens at fertilization
the first sperm to penetrate oocyte membrane wins
triggers depolarization of oocyte
sperm nucleus enter oocyte and meiosis 2 is complete
What happens after fertilization
Day 1: Fertilization
Day 2-4: Cell Division takes place
Day 4-5: Blastocyte (cell complex) reaches uterus
Day 5-9 Blastocyte implants on uterus
Human chorionic gonadotropin (hCG)
fertilization hormone that maintains the corpus luteum and prevents next menstrual cycle
how does hCG maintain corpus luteum?
by increased progesterone levels to keep endometrium intact
it also inhibits pituitary- preventing negative feedback
role of placenta
performs role of digestion, renal, and respiratory system for fetus
Fill in the blank.
______ is a temporary endocrine gland.
placenta
what hormone does the placenta release
it converts cholesterol to progesterone
how can the placenta produce estrogen
from receiving DHEA from fetal adrenal cortex
Function of hCG
maintain corpus luteum
Function of progesterone
suppress uterine contraction and
function of estrogen
uterine and breast duct development
function of human placental lactogen
diverts energy from the mom to the baby
stimulates maternal lipolysis- and breakdown of fats for baby
First trimester
0-12 weeks, embryonic development
Second Trimester
12-28 weeks, fetal development
Third Trimester
28 weeks-delivery, fetal maturation
Maternal Adaptation to Pregnancy
Renal: increased vasopressin, increased water retention
Cardiovascular: increased output
Immune: partially suppressed m
Calcium Homeostasis: more bone resorption (bone is broken down)- calcium transfers to fetus
calcitonin also increases
What triggers labour?
Relaxin in released from ovary and placenta loosens and causes cervix to soften
the trigger is fetus dropping lower in the uterus causing cervical stretch, releasing oxytocin
What hormones are increased during labour
estrogen and oxytocin in uterus
fetal cortisol
CRH
Prostaglandins
is progesterone and estrogen important for milk production
although it is important for development of mammary glands, it inhibits milk release until after birth
What hormones are responsible for milk production
prolactin stimulate milk producing cells
oxytocin causes constriction and squeezing of myoepithelial cells which release milk from duct
What regulates the release of oxytocin and prolactin from the pituitary
a baby’s cry and the baby sucking the nipple
