Embryology

Question 1

What derives from the septum transversum?

Answer 1

central tendon of diaphragm

Question 2

What derives from the pleuroperitoneal membrane?

Answer 2

body of diaphragm

Question 3

Congenital Diaphragmatic Hernias are most common on ____ side and prevent proper development of ____.

Answer 3

left / lungs

Question 4

During week 3, ____ forms between the splanchnic and somatic lateral plate mesoderm.

Answer 4

intraembryonic coloem

Question 5

____ allow communication between the developing thorax and abdomen.

Answer 5

pericardioperitoneal folds

Question 6

During week 3, vasculogenic cells cluster around the cranial portion of trilaminar disc to form the ____.

Answer 6

endocardial tube

Question 7

Fused portion of the endocardial tube forms the ____.

Answer 7

primitive heart tube

Question 8

Unfused ends of the endocardial tube form the ____.

Answer 8

aortic arch arteries

Question 9

During cardiac looping, ventricles curve ____ and ____, while atria moves ____ behind the great vessels.

Answer 9

caudal & ventral / upward

Question 10

____ is a ventral outpocketing of the foregut.

Answer 10

respiratory diverticulum

Question 11

____ closes the respiratory diverticulum off from the esophagus below the level of the larynx.

Answer 11

tracheoesophageal septum

Question 12

Lung bud branches into primary branches- ____, secondary branches- ____, and tertiary branches- ____.

Answer 12

R & L lungs / lobes / segments

Question 13

The 4 stages of lung development are ____, ____, ____, and ____.

Answer 13

pseudoglandular, canalicular, terminal sac, and alveolar

Question 14

Functional alveoli first appear in the ____ stage of lung development.

Answer 14

terminal sac

Question 15

____ bypasses pulmonary circulation in the fetus; between the R & L atria. Becomes the ____ after birth.

Answer 15

foramen ovale / fossa ovalis

Question 16

____ bypasses pulmonary circulation in the fetus; between the aorta and pulmonary trunk. Becomes the ____ after birth.

Answer 16

ductus arteriosus / ligamentum arteriosum

Question 17

____ bypasses the hepatic portal system in the fetus; between the umbilical vein and IVC. Becomes the ____ after birth.

Answer 17

ductus venosus / ligamentum venosum

Question 18

____ bypasses the hepatic portal system in the fetus; between the placenta and ductus venosus. Becomes the ____ after birth.

Answer 18

umbilical vein / round ligament

Question 19

____ delivers depleted blood from the fetus to the placenta. Becomes the ____ after birth.

Answer 19

umbilical arteries / medial umbilical ligaments

Question 20

During week 3/4, folding incorportates the endoderm-lined gut tube into the embryo and creates mesenteries within the ____ that lines it.

Answer 20

lateral plate mesoderm

Question 21

The ____ and ____ support structures supplied by the celiac trunk.

Answer 21

dorsal mesogastrium / mesoduodenum

Question 22

The ____ supports structures supplied by the superior mesenteric artery.

Answer 22

mesentery proper

Question 23

The ____ supports structures supplied by the inferior mesenteric artery.

Answer 23

mesocolon

Question 24

The ____ gives rise to the greater omentum. Meanwhile the ventral portion also gives rise to the ____.

Answer 24

dorsal mesogastrium / lesser omentum

Question 25

Foregut starts caudal to diaphragm and rotates to the ____ and ____ to produce the curvatures of the stomach.

Answer 25

right / cranially

Question 26

Distal foregut gives rise to the proximal 1/3 of the ____.

Answer 26

duodenum

Question 27

____ is a ventral outpocketing of the duodenum into the ventral mesogastrium, and gives rise to the ____.

Answer 27

hepatic diverticulum / liver

Question 28

____ and ____ also arise from the hepatic diverticulum.

Answer 28

gall bladder / bile ducts

Question 29

Two ____ buds arise from the duodenum into the dorsal and ventral mesoduodenum.

Answer 29

pancreatic

Question 30

During stomach rotation, ____ fuse and one ____ degrades.

Answer 30

pancreatic buds / pancreatic duct

Question 31

Midgut gives rise to the distal 2/3 ____, jejunum, ileum, cecum, appendix, asending colon, and 2/3 ____.

Answer 31

duodenum / transverse colon

Question 32

Distal tip of midgut loop is still attached to the yolk sac by the ____.

Answer 32

vitelline duct

Question 33

Midgut loop ____ into the umbilical cord as it elongates and rotates.

Answer 33

herniates

Question 34

Small intestine bulges to the ____ and retracts as ____ arches over the top.

Answer 34

right / large intestine

Question 35

Meckel's diverticulum is an incomplete degradation of the ____, which can gain pancreatic properties and breakdown the wall of the ileum allowing leakage.

Answer 35

vitelline duct

Question 36

____ is a condition not compatible with life, in which the gut tube never retracts, preventing the body wall from closing.

Answer 36

omcephalocele

Question 37

Hindgut gives rise to the distal 1/3 transverse colon, descending and sigmoid colon, and the ____.

Answer 37

cloaca

Question 38

Ectodermal thickening and invagination opens hindgut to form the ____.

Answer 38

anal canal

Question 39

____ demarcates the line between endoderm and ectoderm within the rectum.

Answer 39

pectinate line

Question 40

Hirschsprung disease is due to a defect in ____, in which parasympathetic ganglia don't form within the colon and it lacks coordinated ____.

Answer 40

neural crest cells / peristalsis

Question 41

During week 3 pre-folding, the ____ develops as a diverticulum of the endoderm from the yolk sac.

Answer 41

allantois

Question 42

The allantois serves to store ___ beyond the capacity of the nephric system, but is not extensively developed in humans.

Answer 42

urine

Question 43

After birth the allantois remains in the ____ umbilical ligament as the ____.

Answer 43

median / urecus

Question 44

During week 3/4, folding leaves the ____ unincorporated in the embryo.

Answer 44

intermediate mesoderm

Question 45

The intermediate mesoderm gives rise to the primary retroperitoneal structures: ____, ____, and ____.

Answer 45

kidneys, urogenital ductal structures, and gonads

Question 46

____ and ____ ridges make up the urogenital ridge within the intermediate mesoderm.

Answer 46

nephrogenic / genital

Question 47

3 sets of kidneys develop from the nephrogenic ridge: ____, ____, and ____.

Answer 47

pronephros / mesonephros / metanephros

Question 48

The ____ kidneys are never functional, but their ducts play an important inductive role in the development of the next sets of kidneys.

Answer 48

pronephric

Question 49

The ____ kidneys become functional around week 5. They filter blood, make urine, and drain it through the ____ to the ____.

Answer 49

mesonephric / mesonephric ducts / cloaca

Question 50

The ____ kidneys are the final set of kidneys formed. The are functional around week ____.

Answer 50

metanephric / 9-10

Question 51

The metanephric kidneys develop as 2 components: ____ and ____.

Answer 51

ureteric bud / metanephric blastema

Question 52

The ureteric bud gives rise to the ____ structures of the neprhic system.

Answer 52

ductal

Question 53

The metanephric blastema gives rise to the ____ of the kidneys.

Answer 53

nephrons

Question 54

____ between the ureteric bud and metanephric blastema allows both to grow and differentiate.

Answer 54

reciprocal induction

Question 55

Lack of pronephric ducts causes ____, a condition not compatible with life.

Answer 55

renal agenesis

Question 56

The genital ridge is the ____ part of the intermediate mesoderm.

Answer 56

medial

Question 57

Up until week 6, the embryo has bipotential ductal structures, the ____ and the ____.

Answer 57

Mesonephric duct / Mullerian duct

Question 58

The genital ridge gives rise to two types of cells: ____ and ____.

Answer 58

cord cells / mesenchyme

Question 59

In males, the cord cells differentiate into ____, which produce ____.

Answer 59

Sertoli cells / MIF (mullerian inhibiting factor)

Question 60

In males, the mesenchyme differentiates into ____, which produce ____.

Answer 60

Leydig cells / testosterone

Question 61

The high levels of testosterone in males allows repurposing of the mesonephric ducts to become the ____.

Answer 61

Wollfian duct

Question 62

The production of MIF by the Sertoli cells in males, promotes degradation of the ____ through apoptosis.

Answer 62

Mullerian ducts

Question 63

In females, cord cells differentiate into ____.

Answer 63

follicular cells

Question 64

In females, mesenchyme differentiates into ____.

Answer 64

stromal cells of the ovary

Question 65

In females, the ____ degrade since there is no testosterone present.

Answer 65

mesonephric ducts

Question 66

The caudal mullerian ducts fuse to form the ____. While the unfused cranial portion forms the ____.

Answer 66

uterus / fallopian tubes

Question 67

The uterus contacts the dorsal side of the ____, which grows towards the uterus and canalizes to form the vagina.

Answer 67

urogenital sinus

Question 68

The distal 2/3 of the vagina is ___, while the proximal 1/3 iis ____.

Answer 68

endoderm / mesoderm

Question 69

The cloaca divides into the ____ and ____ spaces.

Answer 69

ventral (urogenital) / dorsal (rectal)

Question 70

As the bladder grows, the caudal ____ are incorporated into the wall to become the trigone.

Answer 70

mesonephric ducts

Question 71

The ____ is an outgrowth of the mesoderrm in the genital region, covered by ectoderm, and lined beneath by a layer of endoderm called the ____.

Answer 71

genital tubercle / urethral plate

Question 72

The ____ folds develop lateral to the genital tubercle, while the ____ folds are even lateral to that.

Answer 72

urogenital / labioscrotal

Question 73

In males, the genital tubercle elongates to form the ____, and the ____ grow down and fuse around it to incorporate the ____ inside as a canal

Answer 73

glans of the penis / urogenital folds / urethra

Question 74

In males, the ____ grow down and fuse to form the scrotum.

Answer 74

labioscrotal folds

Question 75

In females, the genital tubercle becomes the ____.

Answer 75

glans of the clitoris

Question 76

In females, the ____ become the labia minora, while the ____ become the labia majora.

Answer 76

urogenital folds / labioscrotal folds

Question 77

In females, the urethral plate becomes the ____.

Answer 77

vestibule