Ms Development

Front 1

mesenchymal origins are derivitives of the _______

Back 1

SOMITES

Front 2

they are under influences of

Back 2

SSH, BMP4, WNT

Front 3

SSH influences

Back 3

somatopleure

Front 4

BMP-4 influences

Back 4

hypaxial mm

Front 5

WNT influences

Back 5

epaxial mm

Front 6

DERMOMYOTOME developes into

Back 6

dermis of skin and skeletal mm

Front 7

SCLEROTOME developes into

Back 7

vertebrae, ANNULUS FIBROSIS of disk and ribs

Front 8

Intermediate mesenchyme (NEPHROTOME) developes into

Back 8

kidney

Front 9

Lateral plate mesenchyme develops into these 2 things

Back 9

1) SPLANCHNOPLEURE
2) SOMATOPLEURE

Front 10

SPLANCHOPLEURE develops into

Back 10

smoothe mm of gut

Front 11

SOMATOPLEURE develops into

Back 11

appendicular skeleton and vasculature

Front 12

NOTOCHORD develops into

Back 12

NUCLEUS PULPOSIS of intervertebral disk

Front 13

intramembraneous bone

Back 13

predominantly in scull (maybe clavical)

Front 14

endochondral

Back 14

intracartilagenous development ( most bones other than skull)

Front 15

condensations of mesenchyme usually precedes what

Back 15

endochondral and intra-membranous bone formation

Front 16

condensantion of mesenchyme --6 steps

Back 16

1) mesencym migrates to area (4th week)
2) condensation of mesenchyme (5th week)
3)CHONDRIFICATION (formation of cartilage) (6th week)
4) begin OSSIFICATION OF PRIMARY CENTERS (wk 7-12)
5) begin ossification of secondary centers and formation of epiphysieal plates (birth to 9y/o)
6) Fusion of EPIPHYSEAL PLATES and end of bone growth, usually 18-25 y/o)

Front 17

patterns of development of joints

Back 17

1) basic embryoic plan
2) development of SYNOVIAL JOINTS
3) development of FIBROCART/FIBROUS JTS

Front 18

develpment of vert & intervvert discs

Back 18

1) each segment develps from parts of 2 SCLEROTOMES (note pattern)
2)CHONDRIFICATION OF PRIMARY OSSIFICATION CENTERS

Front 19

development of sacrum

Back 19

1. union of 5 vert segments
2. all elements (costal part, vertebral arch, centrum0 develop from separate cartilaginous models
3. bony vert arch fuses w/ transverse processes at 2-5 y postnatal. these unite w/ bony centrum at 8 years
4. epiphyseal plates between sacral segments fuse sequentially after puberty, with lowest segments fusing first

Front 20

spinal bifida

Back 20

late closure of caudal neuropore results in delay of inductive signal for neural arch until the point where the mesenchyme is not responsive to such a signal (hense, no neural arch forms).

Front 21

hemivertebra

Back 21

failure of sclerotome to divide and migrate, resulting in abnormal vertebral segment

Front 22

origins of body wall musculature

Back 22

undifferentiated somites change to dermomyotome (under dorsal influence of Wnts & BMP-4). At the same time, the more ventral sclerotome differentiates under the ventral influence of shh (from the notochord) The mesodermal cells of the DERMOMYOTOME (in the head region called the somitomere) differentiate into MYOBLASTS (embryonic period) which fuse to form skeletal mm during the fetal period. The dermotome splits off a group of cells between the dermomyotome and the sclerotome, originally called the 'myotome'

Front 23

primary divisions of embryonic musculature

Back 23

epaxial and hypaxial

Front 24

EPAXIAL

Back 24

'myotome' origin. Deep back mm, innervated by dorsal rami of spinal nn

Front 25

HYPAXIAL

Back 25

'dermotome' origin: migrates outside of the blastimal skeleton form SOMATOPLEURE, contributes with appendicular and body wall musculature. Innervated by ventral rami of spinal nn

Front 26

pattern of nn mm association

Back 26

1) myoblasts develop (4th-5th week)
2)axons grow out of CNS in 5th week and follow migrating myoblasts.
3) Axons divide into preaxial (flexor) and postaxial (extensor) groups of mm
4) Axons begin migration to final location during 5th to 6th week.
5. Around 17th -20th week, mm begin to fx and you will see mvmt of limbs
6. Around 2 yrs postnatal, myelination of lower extremities

Front 27

Development of mm fibers

Back 27

1. elongated, elongated migrating embryonic myoblasts find their final locations and fuse into multinucliate primary and secondary myotubes
2. the myotubes develop myofilaments and become striated, becoming mm fibers

Front 28

Apppendicular skeleton: general pattern of development

Back 28

posterior part of limb bud developes sonic hedgehog gene for posterior bone sxs, and this gene is progressively expressed more anteriorly.

Front 29

Upper limb has ______ rotation

Back 29

LATERAL (OUTWARD)

Front 30

in upper limb, cells migrating anterior to axis of limb are under _______ innervation

Back 30

PREAXIAL (flexor; ventral)

Front 31

in upper limb, cells migrating posterior to axis of limb are under _______ innervation

Back 31

POSTAXIAL (extensor; dorsal) innervation

(NB-migration can change fx w/o changing innervation e.g., brachioradialis)

Front 32

general patterns in upper limb developemnt

Back 32

once myoblasts migrate into area, they separate into superficial and deep groups (if appropriate), and then into horizontal groups (e.g., extensor crpi ulnaris, extensor digitorum, extensor carpi radialis).

Proximal parts of the limb develop first, distal parts develop later

Front 33

syndactily

Back 33

fusion of digits (failure of appropriate cell death

Front 34

polydactily

Back 34

extra digit (abnormal induction of a 6th digit)

Front 35

Amlia

Back 35

absense of a limb

Front 36

meromelia

Back 36

absence of part of a limb

Front 37

lobster claw hand

Back 37

absence of the 3rd digit, fusion of 4th and 5th

Front 38

lower limb general pattern of mm development is similar to upper limb with only minor differences T/F

Back 38

T

Front 39

Lower limb has _________ rotation

Back 39

MEDIAL (INWARD) ROTATION

changes in position will alter relative location of preaxial and postaxial mm for leg

Front 40

malformations of lower limb are similar to those of uppper limb-- give two notable exceptions

Back 40

1. CLUB FOOT
2. congenitally dislocated hip (CDH)