Development

Question 1

Derived from paraxial mesoderm

Answer 1

Skeletal muscle

Question 2

Smooth muscle from ECTODERM

Answer 2

Pupillary, mammary gland and sweat gland muscles

Sphincter and dilator muscles of the pupil, muscle tissue of mammary gland, sweat glands

Question 3

Smooth muscle differentiates from

Answer 3

Splanchnic mesoderm surrounding the gut and its derivatives

Question 4

Cardiac muscle differentiates from

Answer 4

Splanchnic mesoderm surrounding the heart tube

Question 5

From the musculature of the axial skeleton, body wall, limbs and head

Answer 5

Somites and Somitomeres

Question 6

Striated skeletal muscle from the occipital region caudally.. Somites form and differentiate into

Answer 6

1) sclerotome
2) dermatome
3) 2 muscle forming regions (VLL & DML)

Question 7

Domain that comprises the regions around the neural tube and contains only somite-derived cells

Answer 7

Primaxial domain

Question 8

Domain that consists of the parietal layer of lateral plate mesoderm together w/ somite cells that have migrated across the lateral somitic frontier

Answer 8

Abaxial domain

Question 9

Two muscle forming regions

Answer 9

Dorsolateral region of the somite (VLL)
Dorsomedial region (DML)

Question 10

Dorsolateral region of the somite expresses the muscle specific gene

Answer 10

MyoD

Question 11

Dorsomedial region expresses the gene

Answer 11

Myf5

Question 12

Migrates to provide progenitor cells for limb and body wall musculature

Answer 12

Dorsolateral region

Question 13

Migrates ventral to cells that form dermatome

Answer 13

Dorsomedial region

Also forms the myotome, myf5

Question 14

Sonic Hedgehog (SHH) is secreted by

Answer 14

1) Notochord

2) floor plate of neural tube

Question 15

Causes the ventral part of the somite to form sclerotome and express PAX1

Answer 15

SHH

Question 16

Function of PAX1

Answer 16

Control chondrogenesis and vertebral formation

Question 17

Activate PAX3 which in turn demarcates dermayotome

Answer 17

WNT PROTEINS

Question 18

Directs the dorsomedial portion of the somite to form epaxial (back) muscles and express Myf5

Answer 18

WNT PROTEINS

Question 19

Mid dorsal portion of the somite is directed to become dermis by

Answer 19

Neurotrophin 3 (NT3), expressed by the neural tube

Question 20

Hypaxial musculature (derived from dorsolateral portion of somite) is influenced by

Answer 20

Wnt proteins and inhibitory BMP-4 protein =activates myoD

Question 21

Hypaxial musculature

Answer 21

Limb and body wall

Question 22

Presence of cross striations in skeletal muscle

Answer 22

End of 3rd month

Question 23

Formation of patterns

Answer 23

Controlled by connective tissue into which myoblast migrate

Question 24

Head region is derived from

Answer 24

Neural crest cells

Question 25

Cervical and occipital regions are from

Answer 25

Somatic mesoderm

Question 26

Origin of body wall and limbs

Answer 26

Somatic mesoderm

Question 27

Small dorsal portion, formed from the dorsomedial cells of the somite

Answer 27

Epimere

end of 5th week muscle cells are collected into two: epimere and hypomere

Question 28

Nerve innervating the epimere

Answer 28

Dorsal primary ramus

Question 29

Nerve innervating the hypomere

Answer 29

Ventral primary ramus

Question 30

Myoblasts of the epimeres form the

Answer 30

Extensor muscles of vertebral column

Question 31

Gives rise to muscle of limbs and body wall

Answer 31

Hypomeres

Question 32

Myoblasts from cervical hypomeres form

Answer 32

Scalene, Genihyoid, prevertebral muscles

Question 33

All voluntary muscles of the ehad region derived from (includes tongue, eye, pharyngeal arches) .. Except the iris, optic cup ectoderm

Answer 33

Paraxial mesoderm

Question 34

In the head

Answer 34

Derived from neural crest cells

Question 35

Limb muscles observed in what week of development?

Answer 35

7th week

Question 36

Elongation of the limb buds, the muscle tissue splits into

Answer 36

Flexor and extensor components

Question 37

Form the conducting system of the heart

Answer 37

Purkinje fibers

Question 38

Muscular system develops from the

Answer 38

Mesodermal germ layer