Musculoskeletal Development (embryo) 11-21-16

Question 1

Sclerotome forms all the axial skeleton except….

Answer 1

sternum (lateral)

portion of skull(neural crest)

Question 2

neural crest cells–>mesenchyme–>

Answer 2

viscerocranium and hyoid bone

Question 3

paraxial mesoderm–> mesenchyme–>

Answer 3

vertebrae, ribs, neurocranium

Question 4

lateral mesoderm–> mesenchyme–>

Answer 4

pectoral girdle, pelvic girdle, limbs and sternum

Question 5

each sclerotome segment has a… portion and a… portion

Answer 5

1. less dense cranial portion

2. dense caudal portion

Question 6

Primaxial domain- dorsomedial lip and a few ventrolateral lip cells will form:

Answer 6

muscles of shoulder, back and intercostals

Question 7

Abaxial domain- most ventrolateral lip myoblasts migrate across the frontier into the lateral plate somatic mesoderm to form:

Answer 7

muscles of infra hyoid, pec major and minor, abs and limbs

Question 8

Primaxial becomes…

Answer 8

Epaxial (dorsal/posterior)

Question 9

Abaxial becomes…

Answer 9

Hypaxial (ventral/anterior)

Question 10

smooth muscle exceptions that are derived from ectoderm

Answer 10

1. sphincter and dilator mm. of iris

2. myoepithelial cells of mammary, salivary and sweat glands

Question 11

Limb bud is a core of…. and is lined by…

Answer 11

• mesenchyme

- surface ectoderm