LECTURE 4 General Embryology IV (NYUCD)
NEWEST EXAM 2026-2027 COMPLETE 50
QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED
(1941) German measles - CORRECT ANSWER: that affected a mother during early pregnancy
caused abnormalities (cataract & heart defects) in the embryo.
(1961) thalidomide - CORRECT ANSWER: - First report linking limb defects to a sedative
thalidomide
- Evidence that drugs could also cross the placenta and produce birth defects --> absence of the
long arms so that head is attached to shoulder = PHOCOMELIA
11-week Human Fetus - CORRECT ANSWER: - 5-7 cm (crown-rump length = top of head to
bottom)
- Swelling of the umbilical cord --> because of physiological herniation taking place
- Digits are well developed
- Irregular skull contours
- Eyes ventrally located --> eyes were originally more dorsal position & moved
12-week Human Fetus - CORRECT ANSWER: - ~ 8 cm (crown-rump length)
- Primary ossification centers formed
- External genitalia recognizable
- Vascularization visible
- Retraction of herniated loops
- Muscular activity
, 18-week Human Fetus - CORRECT ANSWER: - ~ 15 cm (crown-rump length)
- Eyebrows and head hair visible
- Outer ears in their final position
28-week Human Fetus - CORRECT ANSWER: - ~ 27 cm (crown-rump length)
- Well-rounded contours
- Most organ systems are functional
- Except respiratory and nervous systems
- Birth at 7 months = 90% survival chance
AMNIOCENTESIS - CORRECT ANSWER: [not enough cells, very long process]
o Approximately 20 to 30 ml of fluid is withdrawn from the amniotic cavity.
o Procedure is performed transabdominally, in the second trimester (15 & 20 weeks).
o The fluid is analyzed for biochemical factors, such as AFP.
o Fetal cells are recovered in the amniotic fluid --> a. Perform karyotyping (several weeks) OR
b. Polymerase chain reaction can be performed to test for specific genetic diseases.
As the fetus grow there is a(n): - CORRECT ANSWER: increase in nutrients demand to provide
to growing organs
> demand is meet by an increase in surface area between maternal and fetal components. Via
development of: CHORIONIC VILI
Birth defect - CORRECT ANSWER: congenital malformation = congenital anomaly
> structural, behavioral, functional, and metabolic disorders present at birth.
NEWEST EXAM 2026-2027 COMPLETE 50
QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED
(1941) German measles - CORRECT ANSWER: that affected a mother during early pregnancy
caused abnormalities (cataract & heart defects) in the embryo.
(1961) thalidomide - CORRECT ANSWER: - First report linking limb defects to a sedative
thalidomide
- Evidence that drugs could also cross the placenta and produce birth defects --> absence of the
long arms so that head is attached to shoulder = PHOCOMELIA
11-week Human Fetus - CORRECT ANSWER: - 5-7 cm (crown-rump length = top of head to
bottom)
- Swelling of the umbilical cord --> because of physiological herniation taking place
- Digits are well developed
- Irregular skull contours
- Eyes ventrally located --> eyes were originally more dorsal position & moved
12-week Human Fetus - CORRECT ANSWER: - ~ 8 cm (crown-rump length)
- Primary ossification centers formed
- External genitalia recognizable
- Vascularization visible
- Retraction of herniated loops
- Muscular activity
, 18-week Human Fetus - CORRECT ANSWER: - ~ 15 cm (crown-rump length)
- Eyebrows and head hair visible
- Outer ears in their final position
28-week Human Fetus - CORRECT ANSWER: - ~ 27 cm (crown-rump length)
- Well-rounded contours
- Most organ systems are functional
- Except respiratory and nervous systems
- Birth at 7 months = 90% survival chance
AMNIOCENTESIS - CORRECT ANSWER: [not enough cells, very long process]
o Approximately 20 to 30 ml of fluid is withdrawn from the amniotic cavity.
o Procedure is performed transabdominally, in the second trimester (15 & 20 weeks).
o The fluid is analyzed for biochemical factors, such as AFP.
o Fetal cells are recovered in the amniotic fluid --> a. Perform karyotyping (several weeks) OR
b. Polymerase chain reaction can be performed to test for specific genetic diseases.
As the fetus grow there is a(n): - CORRECT ANSWER: increase in nutrients demand to provide
to growing organs
> demand is meet by an increase in surface area between maternal and fetal components. Via
development of: CHORIONIC VILI
Birth defect - CORRECT ANSWER: congenital malformation = congenital anomaly
> structural, behavioral, functional, and metabolic disorders present at birth.
