Embryology

Question 1

Process of the formation of the trilaminar embryo

Answer 1

gastrulation

Question 2

During fertilization, spermatozoon enters ovum by puncturing what non-cellular structure?

Answer 2

Zone pellucida

Question 3

Refers to cavity without cells, that is formed by permeation of fluid into morulae

Answer 3

blastocele (blastocyst cavity)

Question 4

Gives rice to placenta

Answer 4

trophoblast (outer cell mass)

Question 5

Heuser’s membrane

Answer 5

hypoblast cells lining blastocyst cavity

Question 6

Gives rise to umbilical cord in the embryoblast

Answer 6

connecting stalk

Question 7

Structure that causes bilaminar embryo to be polarized

Answer 7

prechordal plate

Question 8

group of specialized cells that migrate through primitive node towards prechordal plate

Answer 8

notochordal process

Question 9

Mesoderm migrates cranially and laterally to prechordal plate to become

Answer 9

cardiogenic mesoderm

Question 10

Most common neonatal tumor that arises from primitive streak

Answer 10

teratoma

Question 11

Right-left patterning of body is influenced by what signaling molecule?

Answer 11

nodal

Question 12

Embryonic layer where CNS is derived

Answer 12

ectoderm

Question 13

Urogenital system is derived from

Answer 13

intermediate mesoderm

Question 14

Neural ganglia arise from

Answer 14

neural crest

Question 15

Failure in cranial neuropore closure results in

Answer 15

anencephaly

Question 16

failure of neural folds to close in time prevents vertebrae from forming properly

Answer 16

Spina bifida occulta

Question 17

Ribs arise from what region of somite?

Answer 17

lateral sclerotome

Question 18

when are secondary oocyte and first polar body formed?

Answer 18

completion of meiosis I by primary oocyte (ovarian cycle)

Question 19

when are mature oocyte (23, 1N) and second polar body formed?

Answer 19

completion of meiosis II (fertilization)