Muscoskeletal Development

Question 1

each sclerotome segment has a less dense portion ___ and a dense portion ___

Answer 1

cranially

caudally

Question 1

skeletal muscle is derived from ___

cardiac muscle is derived from ___

smooth muscle is derived from ___

Answer 1

paraxial mesoderm

intraembryonic splanchnic mesoderm

intraembryonic splanchnic mesoderm

Question 1

mesenchyme will differentiate as ___ in digits due to AER induction to fully separate the digits

Answer 1

hyaline cartilage

Question 3

what bones are formed by endochondral ossification?

Answer 3

most bones (limbs & base of skull)

Question 4

what forms digits in AER?

Answer 4

apoptosis

Question 4

by end of 6t week, mesenchyme is condensing to form these outlines of future digits with webbed appearance

Answer 4

digital rays

Question 5

thoracic & sacral are ______.

cervical & lumbar are ____.

Answer 5

primary curvatures (develop during fetal period)

secondary curvatures (develop after birth- told hold head up, and to walk)

Question 6

separates the paraxial mesoderm from lateral plate somatic mesoderm

Answer 6

lateral somitic fronteir

Question 7

premature closure of suture (s)

Answer 7

craniosynostosis

Question 7

at week 12, what is present in all long bones?

Answer 7

ossification centers

Question 8

Identify 1-3.

Answer 8

1. anterior fontanelle
2. posterior fontanelle
3. sphenoid fontanelle

Question 8

somites differentiate into __, ___, & ___

Answer 8

sclerotome

myotome

dermatome

Question 9

what bones are formed by intramembranous ossification?

Answer 9

facial bones & some flat bones of skull

Question 9

Identify 1-2.

Answer 9

1. ectodermal lining
2. mesenchyme

Question 10

when does sphincter muscle of iris constrict?

when does dilater open?

Answer 10

bright light, when you dislike person

in response to sympathetic NS

Question 10

all development is usually in what direction?

Answer 10

cranial to caudal

Question 11

difference between endochondral & intramembranous ossification?

Answer 11

no cartilage model 1st in intramembranous ossification

Question 11

Each myotome divides into ___ & ____

Answer 11

epaxial group (dorsal)

hypaxial group (ventral)

Question 12

in what direction does the limb grow?

Answer 12

proximally to distally

Question 14

Identify.

Answer 14

sclerotome

Question 15

in 6th week, condensed mesenchyme appears at ___

Answer 15

joint interzones

Question 15

forms all of axial skeleton except for sternum and a portion of the skull

Answer 15

paraxial mesoderm (sclerotome)

Question 16

what forms the connective tissue of the limb (cartilage, bone, dermis, blood vessels)

Answer 16

mesenchyme

Question 17

Identify 1-4.

Answer 17

1. neural tube
2. scleratome
3. dermatome
4. myotome

Question 17

which limbs appear 1st?

Answer 17

upper limbs

Question 17

absence of entire limb

Answer 17

amelia

Question 19

Identify.

Answer 19

annulus fibrosis of intervertebral disc

Question 20

smooth muscle is derived from \_\_\_

Answer 20

ectoderm

Question 21

the inferior 2/3 of ___ & the superior 1/3 of ___ form the C5 vertebrae.

Answer 21

C5 C6

Question 21

the upper limb rotates 90 degrees \_\_\_ the lower limb rotates 90 degrees \_\_\_\_

Answer 21

laterally medially

Question 22

some of dense portion of sclerotome forms annulus fibrosis, remaingin dense portion fuses with less dense portion to form vertebral body

Answer 22

resegmentation

Question 22

Identify.

Answer 22

lateral somitic fronteir

Question 23

some ventrolateral myoblasts will migrate across fronteir into lateral plate somatic mesoderm to form \_\_\_\_

Answer 23

skeletal muscle of limb

Question 24

which muscles of eye are derived from neuroectoderm?

Answer 24

sphincter pupillae & dilator pupillae of the iris

Question 25

when do limb buds emerge?

Answer 25

end of wk 4

Question 27

3 types of joints?`

Answer 27

fibrous cartilaginous synovial

Question 27

grow out as lateral extensions of costal processes developing from thoracic vertebrae, & wrap around anteriorly

Answer 27

ribs

Question 29

Identify.

Answer 29

sternal bands

Question 30

extra digits

Answer 30

polydactyly

Question 31

in what direction do somites form?

Answer 31

cranially to caudally

Question 31

each spinal nerve divides into a ___ & \_\_\_\_

Answer 31

dorsal primary ramus ventral primary ramus

Question 33

Identify.

Answer 33

paraxial mesoderm

Question 34

Identify 1-4.

Answer 34

1- Cervical 2- Thoracic 3- Lumbar 4- Sacral

Question 35

bones of face, portion of neurocranium, and hyoid bone are formed from \_\_\_

Answer 35

neural crest cells

Question 36

What are these bones derived from? What type of ossification occurs?

Answer 36

neural crest cells intramembranous ossification

Question 37

innervated by ventral primary rami

Answer 37

hypaxial muscles

Question 38

The viscerocranium is mostly formed from neural crest of which arches?

Answer 38

1st 2 pharyngeal arches

Question 40

joint interzone gives rise to...

Answer 40

ligaments, synovial membrane, menisci

Question 42

At which vertebral level is there a spinal nerve, but no vertebral body?

Answer 42

C8

Question 43

when does limb rotation occur?

Answer 43

week 7

Question 44

at birth, what is status of limb ossification?

Answer 44

diaphysis completely ossified, epiphysis still cartilagenous

Question 44

absence of part of a limb

Answer 44

meromelia

Question 45

Identify.

Answer 45

digital ray

Question 47

premature closure of sagittal suture

Answer 47

scaphocephaly

Question 48

enlarged membranous spaces where 2+ bones meet

Answer 48

fontanelles

Question 50

when does endochondral ossification of limb bones occur?

Answer 50

at end of 8th week

Question 51

what areas of long bone ossify after birth?

Answer 51

epiphysis

Question 52

pectoral & pelvic girdles, limb bones, sternum all formed from \_\_\_\_\_

Answer 52

lateral plate mesoderm

Question 53

Identify 1-3.

Answer 53

1. dorsomedial muscle cells 2. dermatome 3. ventrolateral muscle cells

Question 55

bone-forming tissue comes from ___ & \_\_\_

Answer 55

paraxial mesoderm & neural crest

Question 56

fewer digits

Answer 56

syndactyly

Question 58

myoepithelial cells of mammary, salivary, & sweat glands are derived from \_\_\_

Answer 58

surface ectoderm

Question 60

vertebral columb ribs, portion of neurocranium is formed from \_\_\_\_\_

Answer 60

paraxial mesoderm

Question 61

Identify 1-3.

Answer 61

1. Costal process 2. Rib 3. Costovertebral joint (a synovial joint)

Question 62

paraxial mesoderm condenses to form cube-like segments called \_\_\_

Answer 62

somites

Question 63

innervated by dorsal primary rami

Answer 63

epaxial muscles

Question 64

fibrous joints uniting the flat bones of the skull

Answer 64

sutures

Question 65

dermatome forms \_\_\_ myotome forms \_\_\_\_ sclerotome forms \_\_\_

Answer 65

dermis of back skeletal muscle vertebrae, ribs, portion of neurocranium

Question 66

Blue areas are derived from \_\_\_\_. Orange areas are derived from \_\_\_.

Answer 66

neural crest paraxial mesoderm

Question 67

Identify 1-2.

Answer 67

1. Progress zone 2. AER

Question 69

induced to form by ribs at ventral midline from lateral plate somatic mesoderm

Answer 69

sternum

Question 71

what forms where costal process meets vertebra?

Answer 71

synovial joint

Question 72

sends signaling factors to nearby mesenchyme during elongation of limbs

Answer 72

AER- apical ectodermal ridge

Question 73

where are sclerotome cells found?

Answer 73

surrounding neural tube & notochord

Question 74

what do somites give rise to?

Answer 74

most of axial skeleton & associated musculature & overlying dermis of back

Question 75

the differences in location of extensor & flexor muscle compartments when comparing the upper limb and the lower limb can be explained by this event

Answer 75

limb rotation

Question 76

Identify.

Answer 76

joint interzone

Question 76

when do 2 sternal bars fuse cranially to caudally?

Answer 76

10th week

Question 77

above C7, spinal nerves... below C7, spinal nerves...

Answer 77

come out ABOVE vertebral body comt out BELOW vertebral body

Question 79

area that keeps cells undifferentiated and rapidly dividing to form more limb tissue

Answer 79

progress zone

Question 80

made up of vertebrae, intervertebral discs, ribs, sternum, and skull

Answer 80

axial skeleton

Question 81

What are these bones derived from? What type of ossification occurs?

Answer 81

both paraxial mesoderm & neural crest intramembranous & endochondral ossification

Question 82

made up of pectoral & pelvic girdles and limb bones

Answer 82

apendicular skeleton

Question 83

what forms the tissue that unites the bones of a joint?

Answer 83

mesenchyme

Question 84

this area of skull forms via endochondral ossification. It is base of skull.

Answer 84

chondrocranium

Question 85

premature closure of coronal suture

Answer 85

brachycephaly

Question 86

skeletal muscle forms from \_\_\_

Answer 86

paraxial mesoderm

Question 87

by end of what week is a complete set of cartilage model formed?

Answer 87

8th wk

Question 89

limb bud has a core of ___ lined by \_\_\_

Answer 89

mesenchyme surface ectoderm

Question 90

when are digits fully separated?

Answer 90

by end of 8th week

Question 91

Identify.

Answer 91

somites