x exam 2 digestive system development

Question 1

primitive tubular gut formed during

Answer 1

body folding (endoderm and splanchnic mesoderm)

Question 2

transient loss of patency

Answer 2

near end of embryonic period rapid proliferation of endoderm occludes lumen

Question 3

eventually, ____ form

Answer 3

vacuoles; and coalesce re-opening the tube; purpose unknown

Question 4

arterial blood supply divides into 3 regions

Answer 4

foregut, midgut, hindgut

Question 5

artery that supplies foregut

Answer 5

celiac a.

Question 6

artery that supplies midgut

Answer 6

cranial mesenteric artery

Question 7

artery that supplies hindgut

Answer 7

caudal mesenteric a.

Question 8

derivatives of parts cranial to celiac artery supplies

Answer 8

pharynx and esophagus

Question 9

celiac artery suppies

Answer 9

stomach, descending duodenum, liver, gallbladder, and pancreas

Question 10

cranial mesenteric artery connected to

Answer 10

yolk sac via yolk stalk

Question 11

derivateves of midgut

Answer 11

ascending duodenum
jejunum
ileum
cecum
ascending colon
oral transverse colon

Question 12

derivatives of hindgut

Answer 12

aboral transverse colon
descending colon
cloaca (rectum an durogenital exit paths)

Question 13

pharyngeal arches give rise to

Answer 13

ventral head and neck structures

Question 14

____ pairs form in squential order from cranial to caudal

Answer 14

6

Question 15

each arch is composed of

Answer 15

outer ectoderm
inner endoderm
core of mesoderm

Question 16

arches are separated by

Answer 16

pharyngeal celft externally (1st -6th) and pharyngeal pouch internally (1-6th)

Question 17

pharyngeal pouch is the

Answer 17

foregut

Question 18

1st pair of pharyngeal arches

Answer 18

mouth and nose

Question 19

1st arches are cranial to

Answer 19

1st pharyngeal pouch

Question 20

1st pharyngeal arch forms

Answer 20

right and left mandibular swellings
right and left maxillary swellings (upper jaw and part of palate)
single, midline frontonasal swelling (part of palate; 2 plates thickend ectoderm-nares)

Question 21

palte formation caudally

Answer 21

oropharngeal membrane

Question 22

roof of mouth rostrally

Answer 22

frontonasal process

Question 23

roof of mouth laterally

Answer 23

maxillary processes of 1st pair pharyngeal arches

Question 24

floor of mouth

Answer 24

mandibular processes of 1st pair pharyngeal arches

Question 25

palate will separate

Answer 25

oral and nasal cavities

Question 26

palate formation forms from

Answer 26

2 primordia associated with roof of stomodeum (primary palate and secondary palate)

Question 27

primary palate forms from

Answer 27

fusion of medial nasal prominences and maxillary prominences to incisive region (insciors, incisive bone, superior labia, rostral most hard palate (rostral to incisive foramen))

Question 28

failure of primary palate to fuse results in

Answer 28

cleft lip, cleft primary palate

Question 29

fused medial nasal prominences becomes the

Answer 29

nasal septum

Question 30

medial nasal processes fuse with

Answer 30

maxillary processes

Question 31

most common defect of primary palate occurs at

Answer 31

maxillary/medial nasal process junction and thus off midline

Question 32

secondary palate

Answer 32

mesodermal projections from maxillary processes= palatine shelves or lateral palatine processes
grow into developing oronasal cavity (lateral-medial)
fuse on midline
(majority of hard palate; caudal to incisvie foramen; all of soft palate)

Question 33

failure of mesodermal projections to fuse

Answer 33

cleft of secondary palate (midline)