Embryology

Question 0

Paraxial mesoderm gives rise to?

Answer 0

vertebral colum, ribs, neurocranium base

“somitic”

Question 1

Lateral plate mesoderm- gives rise to?

Answer 1

pectoral/pelvic girdle
limbs
sternum
(somatic and splanchnic)

Question 2

Limb development

Answer 2

5 weeks- budding w AER (apical ectodermal ridge)
5-6 weeks- limb mesenchyme –> chondrocytes
6 weeks- terminal limb flattens, cell death separates digits
12 week- endochondral ossification

Question 3

Vertebral column development

Answer 3

mesoderm (paraxial)–> somite –> sclerotome –> vertebral column
(sclerotome separates at intersegmental mesenchyme)
4 weeks

Question 4

myotomes –>

Answer 4

muscle

Question 5

hypexial vs epaxial

Answer 5

hypexial (dorsal)

epaxial (ventral) muscles

Question 6

ZPA? defect?

Answer 6

zone of polarizing activity

if on both sides –> mirror image digits

Question 7

Syndactyly v brachydactyly v polydactyly

Answer 7

Syn- no apoptosis –> fused digits
brachy- short digits
poly- extra digits