Musculoskeletal & limb development

Question 1

Periaxial mesoderm forms what

Answer 1

neurocranium & torso

Question 2

paraxial mesoderm initially forms ____ which tontinue to form beginning week 4 to form ___

Answer 2

somitomeres

somites

Question 3

What is the difference b/w somitomeres and somites

Answer 3

somitomeres are not as organized

Question 4

what is the nature of somite and its components

Answer 4

segmented - are discreet

Question 5

sclerotome differentiates into what

Answer 5

cartilage, bone, joints of axial skeleton, neurocranium

Question 6

what part of body has sclerotom and somite?

Answer 6

spine

Question 7

does spinal cord or neural tube move?

Answer 7

no

Question 8

what moves around the spinal cord

Answer 8

sclerotome

Question 9

as the neck grows what happens to the vertebrae

Answer 9

vertebrae will float up

Question 10

what happens to myotome as baby grows

Answer 10

muscles stretch - muscles dont float up with vertebrae as spinal cord gets bigger, they stretch

Question 11

what happens to arteries in back as baby grows

Answer 11

they will stretch with the muscles

Question 12

what happens to nerves in back as baby grows

Answer 12

they will stretch

Question 13

where do ribs originate from?

Answer 13

back - grow from thoracic vertebra in paraxial mesoderm

Question 14

where do ribs grow through

Answer 14

the lateral plate mesoderm

Question 15

why is sternum unique?***

Answer 15

It comes from parietal lateral plate mesoderm

Question 16

neurocranium is formed from what two parts

Answer 16

paraxial mesoderm & neurocrest cells

Question 17

what is viscercanium formed from

Answer 17

neural crest cells only

Question 18

limb buds derived from what**

Answer 18

parietal lateral plate mesoderm

Question 19

what week are limb bones and CT formed

Answer 19

6-8

Question 20

what is the last thing to form after bone

Answer 20

arteries and nerves

Question 21

Myotome is divided into what two things

Answer 21

ventrolateral lip & dorsomedial lip

Question 22

ventrolaterl lip forms what

Answer 22

msucles in front (limb and torso)

Question 23

dorsomedial lip forms what

Answer 23

muscles in back

Question 24

paraxial mesoderm from somite migrate from somatomeres down to what

Answer 24

pharyngeal arches

Question 25

skeletal muscles of face go through what

Answer 25

pharyngeal arches

Question 26

do skeletal muscle of torso touch pharyngeal arches

Answer 26

no

Question 27

what innervate the muscles in the pharyngeal arches

Answer 27

cranial nerves

Question 28

where is hypomere located

Answer 28

anterior body

Question 29

by 5th week, dorsomedial myoblasts collect into what region

Answer 29

epimere

Question 30

by end of 5th week ventrolateral myoblasts develop into what

Answer 30

hypomere muscles of anterior body

Question 31

dorsomedial myoblasts form what

Answer 31

muscles of dorsal body

Question 32

dorsomedial myoblasts form what

Answer 32

muscles of dorsal body

Question 33

in the torso do muscles keep their segmented nature

Answer 33

yes

Question 34

what forms limb

Answer 34

ectoderm, parietal laterl plate mesoderm, paraxial mesoderm

Question 35

what is not a part of the limb

Answer 35

endoderm

Question 36

is endoderm part of the limb

Answer 36

no

Question 37

before muscles grow out what is there

Answer 37

CT core, bones, then the muscles come in

Question 38

what is at the end of the primitve rim that sends out signals to tell it to grow and not diffeerentiate

Answer 38

apical ectodermal ridg

Question 39

what is responsible for proximal-distal length of limg

Answer 39

apical ectodermal ridge

Question 40

what does AER stand for

Answer 40

apical ectodermal ridge

Question 41

Why do we all have the thumb on the same side

Answer 41

induction signals from retinoic acid that forms gradient so you know which side of limb to put thumb, etc

Question 42

what is the importance of retinoic acid

Answer 42

creates gradient so things develop in right spot

Question 43

lateral has what kind of levels of reinoic acid and why si that important

Answer 43

high, it tells body where to put thumb, pinky, etc.

Question 44

upper limbs rotate how many degrees and what direction

Answer 44

90 degrees dorsolaterally

Question 45

common interosseaus does what initially

Answer 45

perfuses entire upper limb bud

Question 46

what does median artery replace

Answer 46

common interosseus as main arterial supply of hand

Question 47

what replaces median artery

Answer 47

radial and ulnar

Question 48

what arteries of upper limb are formed last

Answer 48

deep artery of arm and joint arteries

Question 49

ischiadic artery starts where

Answer 49

high up in gluteal region

Question 50

what does ishiadic artery perfuse intiially

Answer 50

entire lower limb

Question 51

why isnt there direct blood supply of posterior thigh

Answer 51

ishiadic artery supplie and then disappears in adulthood

Question 52

what does ishiaidic form before regressing

Answer 52

anterior tibial & inferior gluteal & foot anastomosis

Question 53

what is cardiac smooth muscle formed from

Answer 53

VLPM

Question 54

do hypomere muscle masses form anterior torso muscles

Answer 54

yes

Question 55

Apical ectodermal ridge forms what

Answer 55

a structure that forms from the ectodermal cells at the distal end of each limb bud and acts as a major signaling center to ensure proper development of a limb.

Question 56

what forms lateral medial proximal distal

Answer 56

retinoic acid

Question 57

What induces the adjacent mesoderm to continue to proliferate and remain undifferentiated in the proximal-distal limb axis?

Answer 57

apical ectodermal ridge (AER)

Question 58

Mesodermal regions will only differentiate into specific structures when what is gone?

Answer 58

apical ectodermal ridge (AER)