Musculoskeletal Development S1M2

  1. What are the two different blocks developed form the paraxial mesoderm (one kind on the caudal end and one on the cranial end)
    Somitomeres on the cranial end, somites on the caudal end
  2. The somites seperate into ventral and dorsal groups called
    • Ventral end called Sclerotome
    • Dorsolateral end forming the dermomyotome
  3. What does the ventral part of the somites (Sclerotome) eventually form
    The vetebral column, surrounding the notochord
  4. What does the dorsolateral end of the somites (dermomyotome) eventually form
    Dermis (Derm) of the skin and skeletal (Myotome) muscles
  5. Each mytome forms what two sections
    Dorsal epimere and ventral hypomere
  6. What develops into the deep (intrinsic) muscles of the back
    Dorsal Epimeres of the mytome
  7. All of the intrinsic muscle of the back are innervated by
    The dorsal rami of the spinal nerves
  8. The prevertebral, intercostal muscles, and abdominal muscles are developed from
    Ventral Hypomeres of the myotome
  9. The vertebral, intercostal, and abdominal muscles are innervated by
    The ventral rami of the spinal nerves
  10. The limb muscles develop from what section
    The ventral lateral edge of the somites
  11. With the elongation of the limb muscles, they split into what two blocks
    • Flexors - Anterior
    • Extensors - Posterior
  12. It what direction does the development of somite progress
    Caudal to Cranial
  13. Somite development is triggered by what do signals
    Shh (coming from the ventral neural tube) and Wnts (dorsal neural tube)
  14. What is a synovial joint made up of
    Mesoderm and connective tissue
  15. The upper limb is made up of mostly what joints
    Fibrous Joints
  16. How are joints developed
    The tissue boundaries are established by suppression of condensation by inhibiting fibronectin and breaking N-CAM (neural cell adhesion molecules) linkages
  17. What type of mesenchyme develops into the joints in a synovial membrane
    Interzonal mesenchyme
  18. Damage to what parts of the bones in a growing child will stunt growth
    • From the elbow I flow, to the knee I flee.
    • Damage to the upper tibia, lower femur, the wrist of the ulna, or the shoulder of the Humerus
  19. What is the rule for when a developing bone closes
    First to form, last to close
  20. Where does cartilaginous bone grow from
    Epiphyseal plate
  21. What are the most important parts of cartilaginous bones
    Epiphyseal plates
  22. What cavity of the cartilaginous bone contains hemopoietic cells
    Medullary cavity
  23. What is the only long bone that doesn't contain a medullary cavity
  24. Cartilaginous bone has what structures
    • Epiphyseal plate
    • Primary and secondary ossification centers
    • A cartilage core
    • Medullary cavity
  25. Where is the primary ossification center in comparison to the secondary ossification in long bones
    Primary is in the shaft, secondary in one end or the other
  26. What is the difference between a primary ossification center and a secondary
    Primary is where the cartilaginous bone starts to grow, secondary is where it grows when it is more mature
  27. What is endochondral bone
    Cartilaginous bone
  28. Where does growth take place in a endochondral bone
    Epiphyseal plates
  29. Segmentation of the somatic mesoderm into vertebrae happens when
    4th to 5th weeks
  30. What is unique about the development of the vertebrae.
    After the cranial half is pierced by the spinal chord and migrates inferiorly, the caudal half of the sclerotome fuses with the cranial half. This puts the spinal chord between the vertebral discs
  31. What does the notochord end up developing into
    The inter-vertebral discs
  32. Ribs develop from
    Mesenchymal costal processes of vertebrae and eventually develop costal vertebral plane joints
  33. Two ventro medial sternal bars of mesoderm develop independently to form
    The Sternum
  34. How do the flat bones of the skull develop
    By intramembranous ossification
  35. The membranous neurocranium (skull around the brain) is formed by
    Flat bones from the mesenchyme deposited by oteoblasts around the brain
  36. The anterior of the skull develops from
    Neural crest cells
  37. The posterior part of the skull develops from
    The paraxial mesoderm
  38. What is a squamae
    A center for ossification in the skull
  39. What are the four different squama on the skull
    Frontal, parietal, temporal, and occipital
  40. Squamae in full development become
    Bosses and external occipital protuberences
  41. What does the membranous Viscerocranium include
    It is the bones of the face, maxilla, mandible, lacrimal, zygomatic, and vomer ect.
  42. Cartilaginous neurocranium is also called
  43. What are the four areas formed form chondrocranium
    • Ethmoid
    • Petrous temporal (section of temporal bone)
    • Sphenoid
    • Occipital
  44. Meckels cartilage (Arch I) Cartilaginous Viscerocranium includes what bones
    The cartilanginous joint of the mandibular bar, also includes the incus and malleus of the inner ear
  45. Reikerts cartilage (Arch II) Cartilaginous Viscerocranium includes what eventual bones
    The upper hyoid bone, and stapes of the middle ear
  46. Arch III CartilaginousViscerocranium includes what bones
    Lower hyoid bone and greater cornu of hyoid bone
  47. Arch IV Cartilaginous Viscerocranium develops into what
    Thyroid cartilage
  48. Arch VI of the CartilaginousViscerocranium develops into what
    Arytenoid cartilage (forms the larynx)
  49. Membranous bones of the skull begin ossification at
    The parietal and frontal eminences
  50. Craniosynotosis is when
    There is premature closure of the sutures in a skull of a fetus
  51. What are the different types of craniosynostosis
    • Scaphocephaly/Dolichocephaly- premature closure of sagittal suture
    • Oxycephaly/Brachycephaly-premature closure of coronal sutureImage Upload 1
  52. What is myogenesis
    The formation of elongated myoblasts from mesenchyme (somites)
  53. What is a myotube
    Developing muscle cell or fiber that are multinucleated cylinders
  54. Cardiac muscle cells differentiate from
    Splanchnic mesoderm
  55. Smooth muscle cells for around the gut arise from
    Splanchnic mesoderm
  56. Smooth muscle cells for around blood vessels arise from
    Somatic mesoderm
  57. Smooth muscle cells for pupillary muscles for the eye, sweat glands, mammary glands, and myoepithelial cells arise from
  58. Cardiac muscle cells from splanchnic mesoderm form
    • Cardiac muscle
    • Purkinje fibers
  59. There are no parasympathetic nerves where
    In the limbs or the body wall
  60. Purkinje fibers are
    Modified muscle cells
  61. Hypaxial musculature is found in what region, and develops into
    Ventral region, the body wall
  62. The Epaxial musculature is found in what region and develops into what muscles
    Dorsal, short and long muscles of the back
  63. AER means
    Apical Ectodermal Ridge, it is found on the ends of developing limbs
  64. Damage to the AER causes
    The limbs not to grow
  65. Dorsal divisions of the limb plexus innervate
    Limb extensor muscles
  66. Ventral divisions of the limb plexus innervate
    Flexor mucles
  67. The muscles of the anterior part of the thigh are innervated by nerves from the
    Posterior division
  68. All extensor muscles come from
    A Posterior division
  69. Hiltons law is
    • Nerves that supply sensory innervation to a joint also supply motor innervation to the muscles that move that joint
    • Example - axillary nerve and lateral brachial cutaneous nerve to shoulder joint
  70. What is the prune belly syndrome
    It is a congenital lack of body wall musculature
  71. What causes prune belly
    Lacking or no migration of myoblasts or neural crest cells around the anterior body wall (myotomal development)
  72. Hirshsprungs disease is
    The result is a section of bowel that is essentially paralyzed
  73. Arthrogryposis multiplex congenita is
    It is also known as joint contractures, and includes the degeneration of motor neurons
  74. Torticollis is
    Shortening of the sternocleidomastoid muscle "wry neck", can be due to doctor pulling the baby out by the head as well as other causes
Card Set
Musculoskeletal Development S1M2