chapter 24

Question 1

gestation

Answer 1

38 week period of development (40 if counting from mother’s last menstrual period)

Question 2

zygote

Answer 2

single cell resulting from union of mother/father cells

Question 3

morula

Answer 3

cluster of identical cells from zygote
occurs in uterine tube generally

Question 4

blastocyst

Answer 4

partially hollowed structure formed from morula before reaching uterus
group of cells within (inner cell mass) becomes embryo while the rest (trophoblasts) differentiate into tissue to support developing fetus

Question 5

embryo vs fetus

Answer 5

embryo: growing offspring from conception to 3 months
fetus: growing offspring from 3 months to birth

Question 6

decidua

Answer 6

maternal portion of the placenta
well-vascularized internal portion of endometrium

Question 7

chorion

Answer 7

embryonic potion of placenta
forms chorionic villi

Question 8

what are chorionic villi

Answer 8

projections that break down endometrial tissue creating venous sinuses with maternal blood
can be taken for genetic testing

Question 9

how many arteries/veins are contained within the umbilical cord?

Answer 9

2 arteries and 1 vein
(arteries house LOW O2 blood and vein houses HIGH O2 blood)

Question 10

ductus venosus

Answer 10

allows blood coming in from umbilical vein to bypass liver

Question 11

foramen ovale

Answer 11

allows for high O2 blood to shunt from right atrium to left atrium (bypassing lungs)

Question 12

ductus arteriosus

Answer 12

allows for high O2 blood to shunt from pulmonary artery to aorta (bypassing lungs)

Question 13

what portions of the umbilical structures persist after birth?

Answer 13

proximal portions of umbilical arteries persist as arteries to urinary bladder

Question 14

what is human chorionic gonadotropin?

Answer 14

hormone secreted by blastocyst after implantation
acts like LH stimulating growth and activity of corpus luteum (meaning high amounts of progesterone and estrogen for about 11-12 weeks)

Question 15

when are miscarriages most likely?

Answer 15

when corpus luteum degenerates and it’s actions are taken over by the placenta

Question 16

what does progesterone do during pregnancy?

Answer 16

• promotes endometrial secretions which nourishes embryo
• maintains endometrium
• decreases uterine muscle’s ability to contract
• prepares breasts for milk excretion

Question 17

what does estrogen do during pregnancy?

Answer 17

promotes enlargement of uterus and breasts

Question 18

what are the 3 hormones produced by the placenta?

Answer 18

placental growth hormone
human chorionic somatomammotropin
relaxin

Question 19

what does relaxin do?

Answer 19

hormone that softens cervix and relaxes sacral joints/pubic symphysis to prepare for birth

Question 20

abortion vs fetal death

Answer 20

abortion is loss before 20 weeks (spontaneous or induced)
fetal death is after 20 weeks

Question 21

what are the 5 features tested for in the APGAR score

Answer 21

• heart rate
• respiratory effort
• muscle tone
• stimulation response
• skin coloration
  tested at 1 minute and 5 minutes after birth

Question 22

what are the 3 hormones that prepare breasts for lactation?

Answer 22

estrogen
progesterone
prolactin

Question 23

papilla

Answer 23

nipple
location of lactiferous duct convergence

Question 24

3 major milestones of embryonic development

Answer 24

nervous system - week 3
heart/blood vessels - week 2
heartbeat - week 4

Question 25

when do males have primitive testes and started to secrete testosterone?

Answer 25

month 2

Question 26

when does the most rapid growth occur?

Answer 26

2nd trimester

Question 27

what is a normal birth weight?

Answer 27

2.7-4.5 kg or 6-10 lb

Question 28

factors triggering labor

Answer 28

1. stretching of uterine muscle stimulates prostaglandin production 2. pressure on cervix stimulates oxytocin release 3. changes in placenta that occur naturally 4. cortisol from fetal adrenal cortex inhibits mother's progesterone production (causes relative increase in estrogen stimulating uterine contractions)

Question 29

what does oxytocin do

Answer 29

released from posterior pituitary stimulates uterine contractions and uterine muscle becomes increasingly sensitive to it throughout pregnancy works in positive feedback loop

Question 30

explain the positive feedback loop of oxytocin

Answer 30

cervical stretching activates stretch receptors in uterine wall these receptors send signals to posterior pituitary to release oxytocin oxytocin stimulates further contractions of uterine muscle opening cervix further continues until child is born and stimulus removed

Question 31

pictocin

Answer 31

synthetic form of oxytocin that can be used to hasten labor

Question 32

partuition

Answer 32

process by which fetus is expelled from the uterus ends when bleeding is controlled

Question 33

describe the first stage of labor

Answer 33

- onset of regular uterine contractions and cervix dilation - cervix becomes thinner with each contraction and further dilation - rupture of amniotic sac can occur at any time

Question 34

describe the second stage of labor

Answer 34

- cervix completely dilated - ends with baby's birth episiotomy may be performed to prevent tears

Question 35

describe the third stage of labor

Answer 35

- begins after child is born - ends with expulsion of afterbirth and bleeding control

Question 36

what is contained in the afterbirth

Answer 36

placenta, amniotic sac, umbilical cord

Question 37

placenta previa

Answer 37

placenta attaches at/near cervix dilation near end of pregnancy can cause separation and fatal drop in O2 supply

Question 38

abruptio placentae

Answer 38

placenta separates prematurely from uterine wall common in multigravidas may require termination to save mother's life

Question 39

placenta accreta

Answer 39

endometrium does not develop properly and placenta attaches to myometrium can cause fatal post-natal bleeding

Question 40

hyatidiform mole

Answer 40

arises from union of abnormal gametes or fertilization of ovum with 2 sperm cells causes benign grape-like cyst growth that can turn into malignant choriocarcinoma

Question 41

gestational diabetes

Answer 41

diabetes first diagnosed during pregnancy hormone hPL appears to play role (induces insulin resistance in mother to spare glucose for fetus)

Question 42

puerperal infections

Answer 42

infections related to birth prevalence has dropped with antibiotics and more sterile techniques

Question 43

ductal carcinoma in situ (DCIS)

Answer 43

precancerous condition originating in milk ducts cannot be felt, have to be diagnosed with mammography