A & P Flashcards
In utero, what is independent of FSH?
primordial follicle
What accelerates growth of 6-12 secondary follicles each cycle?
Estradiol from ovary (FSH)
How long does it take for a dominant follicle to be established?
about 1 week others die (atresia)
What surge shifts production from estrogen to progesterone?
LH surge
What is released in response to progesterone & increases blood flow & leads to plasma transudation into follicle?
vasodilators- prostaglandins, histamine, bradykinin
Stigma is extruded & ruptures after weakening by what?
Plasmin & collagenase enzymes
The excavated follicle becomes what?
corpus luteum
In the absence of_______________, the follicle will not rupture
LH surge
“Corona rediata” refers to what?
when the stigma ruptures & ovum is carried w/in fluid & cells
The outer wall of___________ swells & allows stigma from center to protrude?
graffian follicle
Estradiol is related to what?
LH & proliferative phase
Progesterone is related to what?
Secratory phase & ovulation
FSH stimulates what?
ovary
What has to happen high in tube in order for implantation to occur?
fertilization of egg
How is a fertilized ovum transported?
weak fluid currents & ciliated tubes
_____________ & ____________ membranes make hCG which sustains _________ through first trimester
placenta & embryonic
luteum
The fertilized egg arrives at 3-4 days & feeds off “_______________” for 2-3 days before implantation
uterine milk
What doe the blastocyst use to penetrate endometrium (decidual reaction)?
plasmin
The fertilized egg is embedded in the stroma by day?
8-12
How is the embryo nurtured?
vaculoles that are formed by dilated blood vessels that invade the fertilized, implanted egg
hCG is initially produced by the __________, then by the ___________?
embryo (trophoblasts), then placenta
hCG does what & for how long?
stimulates progesterone (steroidogenesis) production by CL. Peaks at about 10 weeks, but declines w/ CL degeneration at around 10-12 weeks.
After hCG declines, who becomes the major site of steroid production?
placenta
HPL
human placental lactogen
secreted into maternal circulation, rises througout pregnancy
protein hormone, like prolactin
What does HPL do?
Metabolic hormone of pregnancy- antagonizes maternal glucose consumption. Implicated in GDM
Hyperemesis gravidarum
morning sickness w/ wt loss, ketonuria, electrolyte imbalance
Digestive system & morning sickness
notion that mother will provide is false
Alk phos & cholesterol increase
Albumin decreases
Integument changes in pregnancy
vascular spiders
melasma/choasma
linea nigra
striae
Relaxin
enlarges ribcage & subcostal diaphragm diameter, volumes & capacities effected by mechanical changes. DOE increases throughout pregnancy
Cardiovascular changes in pregnancy (often volume related)
CO changed by HR & SV CO positional BP decreased early, then compensated BP higher than pre-preg=MONITOR altered heart sounds
Never use what kind of BP medication in pregnancy d/t renal damage
ACEi
Renal changes in pregnancy
kidneys enlarge
increased GFR increases CrCl
glucose load & excretion increases
trace protein in UA-NORMAL from expanded vol, enhanced perfusion
Bladder changes
reduced capacity
increased pressure
Hematologic changes
BV increased at 6 weeks
physiologic anemia
2 fold nml risk of embolism
hypercoaguable state
Breast changes
tenderness, tingling
hypertrophy (progesterone)
colostrum expression pre-partum
darkening of nipples
Musculoskeletal changes
lumbar lordosis
unsteady gait w/ separation of PS (relaxin effect)= fall risk
Reproductive system changes
increased d/c
endocervix converts to ectocervix
mucus plug forms
uterine volume increases x500
Oxygen exchange with maternal circulation occurs where in the placenta?
chorionic villi
How saturated is the umbilical vein?
80%
What is thought to protect the fetal heart as an anatomic/physiological sphincter?
ductus venosus- it bypasses the liver
90% of the blood leaving the rt ventricle flows through ____________ into aorta
ductus arteriosus
In fetal circulation, the blood in the SVC & rt hepatic vein flows through what valve?
tricuspid
What channels blood from the IVC & left hepatic vein to the left atrium (30% CO)
crista dividens
What EXTRACTS oxygen in the fetus?
pulmonary circuit
Poorly oxygenated blood from the lungs mixes with what?
shunted blood
Fetal aortic blood oxygenated by what %
65%
Descending aorta carries relatively deoxygenated blood to
caudal fetus (35%) & placenta (65%)
Ductus arteriosus
20% functionally closed at 24 hrs
82% by 48 hrs
100% by 96 hrs
Closure initially functional, d/t changes in pressure, but over time endothelial cell growth & deposition of fibrous tissues seals them
Reduced resistance in lungs invites flow & a buildup of ___________with loss of maternal flow stimulates_____________
CO2
respiratory drive
Small shunt of blood persists from_______ to left pulmonary artery for 24-48 hrs after birth
aorta
greater workload on rt ventricle in fetus means that wall of rt ventricle is____________until about 1 month of age
thicker
after about 1 mo old it atrophies
What happens during 3rd week of development
gastrulation forms trilaminar embryo notochord formation neural tube formation neural crest formation somite formation coelom blood vessels & blood chorionic villi increases surface area of chorion for exchange of nutrients
notochord
primordial axis of the embryo
neural tube
CNS primordium
Somite
musculoskeletal primordia
coelom
body cavity
What happens between 4-8 weeks of development (organogenetic period)
all major organ systems form
heart moves ventrally as brain forms
embryonic disc folds in 4th wk=C-shaped cylindrical embryo
incorporation of yolk sac & formation of gut in 4th wk
eyes develop when
5-8 weeks
ears develop when
4-5 months
What happens during the 9th week of development
head is 1/2 crown rump length
legs are short, arms reach final relative length 12th week
external genitalia differentiating 9-12th weeks
intestinal coils near umbilical cord move into abdomen by end of 12th week
blood formation shifts from LIV to SP 9-12 weeks
14 weeks
skeletal ossification & coordinated limb movements
9th week-birth is what period?
fetal period
scalp hair pattern determined by
13-16th week
21-25 weeks
significant wt gain
26 weeks
lungs & vasculature mature enough to support respiration
CNS mature enough to direct rhythmic breathing & control body temp
28 weeks
bone marrow assumes erythropoiesis
30 weeks
pupillary light reflexes can be elicited
35 weeks
grasp & orientation to light
36 weeks
head & abd circumference equal
37 weeks
fetal foot slightly longer than femur
