embryology

Question 1

ectoderm forms what?

Answer 1

skin
cns
pns
glands

Question 2

endoderm forms what?

Answer 2

epithelial lining of git and resp tract
liver
pancreas

Question 3

mesoderm forms what?

Answer 3

muscles, bones, cartilages, spleen etc

Question 4

organogenesis occurs when?

Answer 4

week 3-8

Question 5

how is gut tube formed?

Answer 5

endodermal lining of yolk sac - formed by folding of embryo

Question 6

how is gut tube still connected ?

Answer 6

conne ted temporarily to yolk sac by vitelline duct

Question 7

ventral and dorsal meaning?

Answer 7

ventral - anterior

dorsal - posterior

Question 8

ventral mesentery splits to? and why?

Answer 8

due to liver growing here

falciform ligament(anterior) and lesser omentum

Question 9

how do organs form from gut tube?

Answer 9

as outpouchings

Question 10

how intestines from from gut tube?

Answer 10

grow first and grow into umbilicord and retract back into abdomen - physiological herniation

Question 11

how does oesophagus form?

Answer 11

as a lung bud forms from front wall of forgot and splits by tracheostomy’s-oesophageal septum into trachea and oesophagus

Question 12

what rotation does the stomach undergo around? and what does it form?

Answer 12

longitudinal axis and anterograde-posterior axis

forming the curves and parts of stomach

Question 13

duodenum forms from? and how does it rotate?

Answer 13

cadual part-end of foregut
and cranial part -start of midgut

duodenum forms c shape as stomach rotates too and presses against it

Question 14

how does liver form?

development depends on?

Answer 14

as a liver bud outgrowth from anterior wall of distal foregut

foregut and septum trasnversum

Question 15

septum transverse forms?

Answer 15

cells, connective tissue and central tendon of diaphragm

Question 16

spleen develops where?

Answer 16

in dorsal mesentery

Question 17

how does pancreas develop?

Answer 17

by two separate pancreatic buds - dorsal and ventral - both outgrowths of duodenum

when duodenum rotates and pulls these buds together and fuse

Question 18

what is the primary intestinal loop?

Answer 18

what the midgut undergoes to form loops of intestine - grows into umbilicus and rotates anti-clockwise around axis of SM artery and retracts back into abdomen

Question 19

omphalocele?

Answer 19

failure of retraction of herniated intestinal loop

Question 20

what SHOULD HAPPEN to vitelline duct?

Answer 20

should obliterate !

Question 21

origins of hindgut development/parts?

Answer 21

endodermal origin - 1/ 3colon to anal canal

ectodermal origin - lower part of anal canal and orifice

Question 22

cloacal membrane? formed how?

Answer 22

formed by ectoderm and endoderm coming in contact with each other

membrane that covers over development of urinary and reproductive organs

Question 23

what should happen to cloaca?

Answer 23

perforates and no longer exists in living being