ABCP BOARD 2026 REVIEW QUESTIONS AND ANSWERS.
What good substances cross the placental membrane? correct answers O2, CO2, H2O, bilirubin,
maternal serum proteins, RBc, IgG, IgA
What harmful substances cross the placental membrane? correct answers 1) viruses: rubella,
HIV, measles, oral conraception, WARFARIN, DILANTIN, Xanax, cocaine, heroin, RH-
antibodies
What does not cross the placental membrane? correct answers maternal chplesterol, Insulin,
Succinylcholine, HEPARIN, bacteria
Which vessel supplies blood to the fetus? correct answers umbilical vein
Which vessels return blood from the fetus? correct answers umbilical arteries
The development of the IV septum begins when? correct answers 27th day of gestation
the blood begins to circulate in the cardiac system by when? correct answers by end of 3rd week
The division of the truncus arteriosus occurs when? correct answers 28th day of gestation
Growthof the atrial septum primum (heart folding) occurs when? correct answers 4th week
The aortic formation occurs when? correct answers 6-9th week
The pulmonary formation occurs when? correct answers 8-12th week
Growth of the septum secundum occurs when? correct answers 6th week (when PFO can occur)
What is considered the embryonic period? correct answers first 2 months (1st 8 wks)
What is considered the fetal period? correct answers months of development after the 2nd week
How many cells are present around the morula by the end of the 3rd day of cleavage? correct
answers 16
***During the later stages of pregnancy, maternal blood is separated from frtal blood by?
a)syncytiotrophoblast only
b) cytotrophoblast only
c) syncytioytophoblast and cytotrophoblast
d) syncytiotrophoblast and fetal endothelium
e) cytotrophoblast and fetal endothelium correct answers syncytiotrophoblast and fetal
endothelium
The maternal and fetal components of the placenta are?
,a) decidua basalis and secondary chorionic villi b) decidua capsularis and secondary chorionic
villi
c) decidua parietalis and tertiary chorionic villi d) decidua capsularis and villous chorion
e) decidua basalis and villous chorion correct answers decidua basalis and villous chorion
***The intervillous space of the placenta contains?
a) maternal blood
b) fetal blood
c) maternal and fetal blood
d) amniotic fluid
e) maternal blood and amniotic fluid correct answers maternal blood
A young insulin dependent diabetic woman in her 1st pregnancy is concerned that her daily
injection of insulin will cause a congenital malformation in her baby. What should the physician
tell her?
a) insulin is highly tetrogenic: discontinue treatment
b) insulin does not cross the placental membrane
c) insulin crosses the placental membrane but is degraded rapidly
d) insulin will benefit her baby by increasing glucose metabolism
e) insulin crosses the placental membrane but is not teratognic correct answers insulin does not
cross the placental membrane
***What is normal amount of amniotic fluid at term?
a) 50 ml
b) 500 ml
c) 1000 ml
d) 1500 ml
e) 2000 ml correct answers 1000 ml
***Which of the following does not pass through the primative umbilical ring?
a) Allantois
b) Amnion
c) Yolk sac
d) Connecting stalk
e) Space connecting the intraembryonic and correct answers Amnion
***Which of the following best describes the placental components of dizygotic twins?
a) 1 placenta, 2 amniotic sacs, 1 chorion
b) 1 placenta, 2 amniotic sacs, 2 chorions
c) 2 placentas, 2 amniotic sacs, 1 chorions
d) 2 placentas, 2 amniotic sacs, 2 chorions
e) 1 placenta, 2 amniotic sacs, 2 chorions correct answers 2 placentas, 2 amniotic sacs, 2
chorions
***a 26 year old pregnant woman experiences repeated episodes of bright red vaginal bleeding
at week 28, week 32, and week 34 of pregnancy. The bleeding spontaneously subsided each
,time. Using ultrasound, the placenta is located in the lower right portion of the uterus over the
internal os. What is the diagnosis?
a) Hydatidiform mole
b) Vasa previa
c) Placenta previa
d) Placenta abruption
e) premature rupture of the amniochorionic membrane correct answers Placenta previa
***a 19 yr old woman in week 32 of a complication-free pregnancy is rushed to the emergency
department because of profuse vaginal bleeding. The bleeding subsides, but afterwards no fetal
heart sounds can be heard, indicating intrauterine fetal death. The woman goes into labor and
delivers a stillborn infant. On examination of the afterbirth, a velamentous placenta is detected.
Although not much can be done at this point , what is the diagnosis?
a) Placenta previa
b) Vasa previa
c) Hydatidiform mole
d) Premature rupture of the amniochorionic membrane
e) amniotic band syndrome correct answers Vasa previa
What is the arterial oxygen saturation od blood from the placenta? correct answers 70%
what is the outer covering of cells on the blastocyst called? correct answers trophoblast
what is the inner cell mass of the blostocyst called?
what does the blastoele develop into? correct answers blastocoele
embryo
what is implantation? when does implantation occur? correct answers attachment of blastocyst to
endometrium
7-8 days after ferilization
After implantation the inner cell mass of blastocyst divides into what 3 primary germ layers?
correct answers 1) ectoderm - upper layer of inner cell mass. boarders blastocoel
2) endoderm - bottom layer of inner cell mass. boarders blastocoel
3) intraembryonic mesoderm
what is the 3 germ layer structure called? correct answers trilaminar embryonic disc
which layer of the embryonic disc do all tissues and organs develop from? correct answers
intraembryonic mesoderm
what is the process called that develops the 3 germ layers of the trilaminar embryonic disc?
correct answers Gastrulation
By what time does the gastrulation occur correct answers day 21 of development
, What is the yolk sac? correct answers endoderm-lined membrane that receives nourishment from
the endometrium.
what is the horseshoe-shaped region of the mesoderm that is located at the cranial end of the
embryonic disc. What does it develop into? correct answers Cardiogenic region, the future heart
where is the early site of blood formation? correct answers yolk sac
what becomes the embryonic part of the placenta? correct answers chorion
the first indicator of gastrulation is the formation of what? caused by what? correct answers
primative streak, proliferation of epiblast cells
the primative streak is composed of what 3 structures? correct answers primative groove,
primative node, primative pit
what tissue layer is involved in placenta formation? correct answers extraembryonic mesoderm
what is the thick plate of mesoderm located on each side of the midline correct answers paraxial
mesoderm
what does paraxial mesoderm become organized into segments known as? correct answers
somitomeres
what do somitomeres 1-7 form into? correct answers pharyngeal arches
what do the remaining somitomeres form into? correct answers pairs of somites
what does the intermediate mesoderm form into? What does the urogenital ridge develop into?
correct answers urogenital ridge
kidneys and gonads
changes involving the ectoderm differentiates into what? what does it form in the future? correct
answers neuroectoderm and neural crest, become nervous system
Vasculogenisis is also called? correct answers angiogenisis
extraembryonic mesoderm forms into which vessels? intraembryonic mesoderm forms into
which vessels? correct answers umbilical vessels
blood vessels within the embryo
***Which germ layers are present at the end of week 3 of development? (day 21)
a) epiblast only
b) ectoderm and hypoblast
c) ectoderm, endoderm
d) ectoderm, mesoderm, and endoderm
What good substances cross the placental membrane? correct answers O2, CO2, H2O, bilirubin,
maternal serum proteins, RBc, IgG, IgA
What harmful substances cross the placental membrane? correct answers 1) viruses: rubella,
HIV, measles, oral conraception, WARFARIN, DILANTIN, Xanax, cocaine, heroin, RH-
antibodies
What does not cross the placental membrane? correct answers maternal chplesterol, Insulin,
Succinylcholine, HEPARIN, bacteria
Which vessel supplies blood to the fetus? correct answers umbilical vein
Which vessels return blood from the fetus? correct answers umbilical arteries
The development of the IV septum begins when? correct answers 27th day of gestation
the blood begins to circulate in the cardiac system by when? correct answers by end of 3rd week
The division of the truncus arteriosus occurs when? correct answers 28th day of gestation
Growthof the atrial septum primum (heart folding) occurs when? correct answers 4th week
The aortic formation occurs when? correct answers 6-9th week
The pulmonary formation occurs when? correct answers 8-12th week
Growth of the septum secundum occurs when? correct answers 6th week (when PFO can occur)
What is considered the embryonic period? correct answers first 2 months (1st 8 wks)
What is considered the fetal period? correct answers months of development after the 2nd week
How many cells are present around the morula by the end of the 3rd day of cleavage? correct
answers 16
***During the later stages of pregnancy, maternal blood is separated from frtal blood by?
a)syncytiotrophoblast only
b) cytotrophoblast only
c) syncytioytophoblast and cytotrophoblast
d) syncytiotrophoblast and fetal endothelium
e) cytotrophoblast and fetal endothelium correct answers syncytiotrophoblast and fetal
endothelium
The maternal and fetal components of the placenta are?
,a) decidua basalis and secondary chorionic villi b) decidua capsularis and secondary chorionic
villi
c) decidua parietalis and tertiary chorionic villi d) decidua capsularis and villous chorion
e) decidua basalis and villous chorion correct answers decidua basalis and villous chorion
***The intervillous space of the placenta contains?
a) maternal blood
b) fetal blood
c) maternal and fetal blood
d) amniotic fluid
e) maternal blood and amniotic fluid correct answers maternal blood
A young insulin dependent diabetic woman in her 1st pregnancy is concerned that her daily
injection of insulin will cause a congenital malformation in her baby. What should the physician
tell her?
a) insulin is highly tetrogenic: discontinue treatment
b) insulin does not cross the placental membrane
c) insulin crosses the placental membrane but is degraded rapidly
d) insulin will benefit her baby by increasing glucose metabolism
e) insulin crosses the placental membrane but is not teratognic correct answers insulin does not
cross the placental membrane
***What is normal amount of amniotic fluid at term?
a) 50 ml
b) 500 ml
c) 1000 ml
d) 1500 ml
e) 2000 ml correct answers 1000 ml
***Which of the following does not pass through the primative umbilical ring?
a) Allantois
b) Amnion
c) Yolk sac
d) Connecting stalk
e) Space connecting the intraembryonic and correct answers Amnion
***Which of the following best describes the placental components of dizygotic twins?
a) 1 placenta, 2 amniotic sacs, 1 chorion
b) 1 placenta, 2 amniotic sacs, 2 chorions
c) 2 placentas, 2 amniotic sacs, 1 chorions
d) 2 placentas, 2 amniotic sacs, 2 chorions
e) 1 placenta, 2 amniotic sacs, 2 chorions correct answers 2 placentas, 2 amniotic sacs, 2
chorions
***a 26 year old pregnant woman experiences repeated episodes of bright red vaginal bleeding
at week 28, week 32, and week 34 of pregnancy. The bleeding spontaneously subsided each
,time. Using ultrasound, the placenta is located in the lower right portion of the uterus over the
internal os. What is the diagnosis?
a) Hydatidiform mole
b) Vasa previa
c) Placenta previa
d) Placenta abruption
e) premature rupture of the amniochorionic membrane correct answers Placenta previa
***a 19 yr old woman in week 32 of a complication-free pregnancy is rushed to the emergency
department because of profuse vaginal bleeding. The bleeding subsides, but afterwards no fetal
heart sounds can be heard, indicating intrauterine fetal death. The woman goes into labor and
delivers a stillborn infant. On examination of the afterbirth, a velamentous placenta is detected.
Although not much can be done at this point , what is the diagnosis?
a) Placenta previa
b) Vasa previa
c) Hydatidiform mole
d) Premature rupture of the amniochorionic membrane
e) amniotic band syndrome correct answers Vasa previa
What is the arterial oxygen saturation od blood from the placenta? correct answers 70%
what is the outer covering of cells on the blastocyst called? correct answers trophoblast
what is the inner cell mass of the blostocyst called?
what does the blastoele develop into? correct answers blastocoele
embryo
what is implantation? when does implantation occur? correct answers attachment of blastocyst to
endometrium
7-8 days after ferilization
After implantation the inner cell mass of blastocyst divides into what 3 primary germ layers?
correct answers 1) ectoderm - upper layer of inner cell mass. boarders blastocoel
2) endoderm - bottom layer of inner cell mass. boarders blastocoel
3) intraembryonic mesoderm
what is the 3 germ layer structure called? correct answers trilaminar embryonic disc
which layer of the embryonic disc do all tissues and organs develop from? correct answers
intraembryonic mesoderm
what is the process called that develops the 3 germ layers of the trilaminar embryonic disc?
correct answers Gastrulation
By what time does the gastrulation occur correct answers day 21 of development
, What is the yolk sac? correct answers endoderm-lined membrane that receives nourishment from
the endometrium.
what is the horseshoe-shaped region of the mesoderm that is located at the cranial end of the
embryonic disc. What does it develop into? correct answers Cardiogenic region, the future heart
where is the early site of blood formation? correct answers yolk sac
what becomes the embryonic part of the placenta? correct answers chorion
the first indicator of gastrulation is the formation of what? caused by what? correct answers
primative streak, proliferation of epiblast cells
the primative streak is composed of what 3 structures? correct answers primative groove,
primative node, primative pit
what tissue layer is involved in placenta formation? correct answers extraembryonic mesoderm
what is the thick plate of mesoderm located on each side of the midline correct answers paraxial
mesoderm
what does paraxial mesoderm become organized into segments known as? correct answers
somitomeres
what do somitomeres 1-7 form into? correct answers pharyngeal arches
what do the remaining somitomeres form into? correct answers pairs of somites
what does the intermediate mesoderm form into? What does the urogenital ridge develop into?
correct answers urogenital ridge
kidneys and gonads
changes involving the ectoderm differentiates into what? what does it form in the future? correct
answers neuroectoderm and neural crest, become nervous system
Vasculogenisis is also called? correct answers angiogenisis
extraembryonic mesoderm forms into which vessels? intraembryonic mesoderm forms into
which vessels? correct answers umbilical vessels
blood vessels within the embryo
***Which germ layers are present at the end of week 3 of development? (day 21)
a) epiblast only
b) ectoderm and hypoblast
c) ectoderm, endoderm
d) ectoderm, mesoderm, and endoderm
