reproduction; birth and lactation

Question 1

birth 1- what do progesterone and estrogen do during pregnancy

Answer 1

the hormones produced by placenta maintain the endometrium/uterine lining, suppress the menstrual cycle and promotes the growth of breast tissue

Question 2

birth 2- what happens to progesterone and estrogen after nine months, why?

Answer 2

levels starts falling, as it’s a signal from fetus when it’s not getting enough fat.

signals uterine contractions/labour

Question 3

birth 3- what occurs at the same time as uterine contractions?

Answer 3

endometrium secretes prostaglandins» initiate uterine contractions.
stretch receptors in cervix stimulates hypothalamus-> signals the pituitary gland to produce o x y t o c i n

Question 4

prostaglandin

Answer 4

stimulates uterine muscle cells to contract even more

Question 5

oxytocin

Answer 5

hormone that continuously stimulates muscles of uterus to contract
+ stimulates placenta to make prostaglandin

Question 6

What is oxytocin controlled by?

Answer 6

positive feedback
small uterine contractions triggers brain to release more oxytocin which strengthens the next contraction until the baby is out.

Question 7

stgofbirth- dilation stage (when water falls)

Answer 7

uterine contractions and oxytocin cause cervix to dilate, amnion breaks and fluid is released

lasts 2-20 hours

Question 8

stgofbirth2- expulsion stage

Answer 8

contractions become so forceful that baby is pushed through cervix -> birth canal
head of baby rotated making it easier to pass through the birth canal

lasts 0.5-2 hours

Question 9

stgofbirth3- placental stage

Answer 9

placenta+umbilical cord = expelled from the uterus

last 10-15 minutes after the baby’s born

Question 10

lactation

Answer 10

after birth, blood lvls of prolactin from the anterior pituitary increase.

Question 11

prolactin

Answer 11

stimulates milk production by mammary glands
as baby suckles prolactin secretion is maintained, oxytocin is released from posterior pituitary.

Question 12

what does oxytocin do during lactation?

Answer 12

causes milk to be released from milk ducts

Question 13

what is the distinct feature of mammals

Answer 13

the prolactin

Question 14

what’s unique about the human’s way of conception

Answer 14

unlike other animals who prefer to give birth alone for the safety of their children, we prefer to have ppl with us to also protect our child.

Question 15

ivf 1- process

Answer 15

1. a woman’s eggs are mixed with sperm in culture dishes
2. incubated for many days&raquo_space; allows fertilized eggs to dvlp -> embryos
3. when they dvlpd embryos -> eight cells each, embryos are carefully inserted into woman’s uterus.

Question 16

positive feedback

Answer 16

oxytocins + prostaglandins cause uterine contractions that stimulate more of these hormones to be produced so it gets more and more stronger by each contraction until they propel baby out of uterus.

Question 17

birth test