Week 12

  1. what are pharyngeal arches
    are a series of externally visible anterior tissue bands lying under the early brain that give rise to the structures of the head and neck
  2. the pharnygeal arches are also called?
    branchial arches
  3. what are the 4 components of the Pahryngeal appartus
    • Pharyngeal arches
    • 2. Pharyngeal clefts
    • 3. Pharyngeal pouches
    • 4. Pharyngeal membranes
  4. where does the pharyngeal pouches comes form
    invagination of the internal endoderm 
  5. where does the pharyngeal cleft  comes form
    invagination of the outer  ectodermal layer
  6. stomodeum
    embryonic mouth
  7. Each pharyngeal arch has
    4 derivative structures
    • 1.Bone & Cartilage
    • 2. Artery
    • 3. Nerve
    • 4. Muscle
  8. Somitomeres
    • Units of paraxial mesoderm in the
    • head, but not distinct as in the body
  9. Somitomeres are involved in formation of..
    Arch 1,2,3 uscles
  10. tongue muscle innevration comes from
    CN XII-  hypoglossal
  11. which arches mainly disappear?
    Left & right aortic arches 1, 2, 5 mostly disappears.
  12. Arch one is the _____ arch and it creates_____
    • “Mandibular”
    • cartilaginous precursor of mandible
    • • malleus, incus
  13. malleus, incus evolved from which type of bones
    jaw bones
  14. which early mammalian bones are synonymous to the incus and malleus respectively?
    articular and quadrate
  15. which muscles comes from PA 1
    • muscles of mastication, temporalis. masseter, pteryoids
    • tensor tympani, tensor veli palatini, anterior bell of the digastric, mylohyoid
  16. function of tensor tympani
    tense eardrum
  17. what Cn comes from PA 1
    trigeminal nerve CN V 5
  18. PA 2 is called the ?
    it creates which bones?
    • hyoid
    • Cartilage & Bone
    • • stapes
    • • styloid process
    • • hyoid (lesser horn, upper body)
  19. PA 2 creates which muscles and nerve?
    • Muscles
    • • muscles of facial expression
    • • stapedius
    • • posterior belly of digastric
    • Nerve
    • • facial (CN VII)
  20. PA 3 is called the ?
    it creates which bones?
    • Carotid 
    • hyoid (greater horn, lower body)
  21. PA3 creates which arteries and nerves ?
    • • internal & external carotid aa.
    • Glossopharyngeal IX 9
  22. PA 3 creates which muscles?
  23. PA 4 creates which cartilages & bones? exception?
    what is it called?
    • laryngeal cartilages except for
    • epiglottis (with PA6)
    • "systemic" arch
  24. PA 4 creates which muscles?
    • cricothyroid, levator veli palatini,
    • constrictors of pharynx, striated mm.
    • of esophagus
  25. PA 4 creates which arteries and nerve?
    • parts of aorta (left arch); right
    • subclavian (right arch)
    • vagus (CN X): superior laryngeal n.
  26. PA 6 creates which cartilage and bones?
    what is it called?
    • the "pulmonary"arch
    • laryngeal cartilages except for
    • epiglottis (with PA4)
  27. Pa 6 creates which muscles ?
    • intrinsic laryngeal muscles except
    • cricothyroid
  28. PA6 creates which arteries and nerves?
    pulmonary aa. and vagus nerve CNX and recurrent larygneal
  29. Image Upload 2 this image represents which pharyngeal arch?
    Branchial arch 1
  30. which clefts and membranes do not contribute to the adult structures>
    Clefts and Membranes 2, 3, 4 do not contribute to adult structures
  31. what is Meckel's cartilages
    part of PA 1 and created the jaw and mandibular bones
  32. what is Reichert's Cartilage
    forms the stylohyoid ligament, styloid process, stapes, and part of the hyoid
  33. Name the follow part of the pharyngeal apparatus 
    Image Upload 4
    • arch
    • cleft
    • pouch
    • membrance
  34. Pharyngeal cleft 1 (PC 1) becomes the external auditory meatus
    external auditory meatus
  35. which cleft contributes to adult structure
    only cleft 1
  36. what happed to PC 2,3, and 4
    come together to create a large sinus but get obliterated
  37. what happens when cleft 2-4 dont get obliterated
    lead to fistulas and clefts
  38. which arch does the left subclavian comes from?
    7th arch
  39. function of stapedius muscles
    attaches to stapes and dampens vibrations of stapes bone so that it does not damage the cochlea particularly from loud noises
  40. the pharyngeal membrane structurally is the ..
    pinched part between the cleft and the pouch
  41. Pharyngeal pouch 1 (PP1) becomes
    the tympanic cavity ad the eustachian tube
  42. the pharyngeal membrane 1 becomes the
    tympanic memebrane
  43. PP2 becomes the
  44. function of tonsils? what are they ?
    they are masses of lymph tissue that trap virus and bacteria and make antibodies to protect against infection
  45. PP 3 creates the
    • thymus 
    • inferior parathyroid glands
  46. PP 4 creates
    • superior parathyroid glands
    • • ultimobranchial body: gives rise to
    • parafollicular/C-cells
  47. what causes a Branchial fistula  ( if it opens externally or internally into the pahrynx) and cysts (arising when cervical sinus )
    when clets 2-4 remain into birth /adulthood usually these obliterate
  48. internal branchial fistula open at
    and is formed from
    internal fistula opens at the palatine tonsil formed from Pouch
  49. external branchial fistula open at
    and is formed from
    opens on the skin of the neck anterior to the sternocleidomastoid m.
  50. How is the tongue formed?
    from swellings in Pharyngeal Arch 1–4
  51. In regards to the tongue what do the 4 arches form?
    • Arch 1 forms mucosa of anterior 2/3 of the tongue.
    • • Arch 2 is overgrown by arch 3 but provides taste innervation to anterior 2/3.
    • • Arch 3 and 4 form mucosa of posterior 1/3 of the tongue
  52. what is the foramen caecum
    • *an opening that occurs btwn the naterior 2/3 and the posterior 1/3 of the tongue , remains as a fossa.
    • The median pit on the dorsum of the posterior part of the tongue, from which the limbs of a V-shaped furrow run forward and outward; the foramen cecum is the point of attachment of the thyroglossal duct and is formed during the embryological descent of the thyroid gland
  53. the posterior 1/3 of the tongue recieve general sensation and taste by CN
    IX glossopharngeal
  54. the anterior 2/3 of the tongue receive motor innervation by CN ___
    except for the palatoglossus muscles which is inv by CN
    • CN XII
    • CNX
  55. the foramen cecaum is a remnant of
    the proximal part of the embryonic thyroglossal duct
  56. where does the thyroid originate from
    • single outpouching of endoderm on the ventral side of arch 1 & 2 int he primordial pharynx
    • the thyroid diverticulum
  57. what is the thyroglossal duct
    a connection of the tongue to the tyroid  via a narrow tube during early dvelopment
  58. what is the path of the developing thyroid
    descend into the neck, passing through developing hyoid bone and laryneal cartilage
  59. what happens when there is an incomplete closure of the thyroglossal
    Thyroglossal duct cyst in the midline of the neck
  60. what happens if a thyroglossal duct cyst is infected..
    it could perforate the skin and cause a sinus
  61. what are the feature of an ectopic thyroid gland?
    there is an additional pyramidal lobe of the thyroid  along the path of the thyroglossal duct  on the midline
  62. Placodes
    • ectodermal discs that form special
    • sense organs of the head.
  63. nasal placode >
    mucosa of nasal capsule
  64. lens placode >
    lens of the eye
  65. otic placode >
    vestibule & cochlea of the ear
  66. neurogenic placodes >
    parts of CNs
  67. nasal placode associated with CN
    • olfactory
  68. lens placode associated with CN
    II optic
  69. otic placode associated with CN
    VIII vestibulocochlear
  70. the actual eyes are formed from
    the evagination of the wall of the brain (neuroectoderm)
  71. Left & right maxillary prominences:
    • upper cheek regions and
    • upper lip
  72. Left & right mandibular
    prominences: form
    • lower jaw, lower
    • lip, and lower cheek regions.
  73. Frontonasal prominence: forms
    the forehead and dorsum/apex of nose.
  74. Lateral nasal prominences forms
    • sides of
    • the nose.
  75. Medial nasal prominences:
    • form the
    • intermaxillary segment that eventually gives
    • rise to the nasal septum, middle part of
    • upper lip, and philtrum (medial cleft).
  76. the maxillary and mandibular prominences are derivatives of arch
  77. The palate forms through two stages
    • Primary palate: extension of the intermaxillary segment from the nasal prominences.
    • • Secondary palate: joining of the palatine process from the maxillary prominences.
  78. define Cleft palate
    • caused by incomplete
    • closure of palate shelves or primary palatine
  79. what is cleft lip
    when maxillary prominence and the medial nasal prominece fail to fuse
  80. frequency of cleft lip/palate?
    Occurs in 1 in ~1,000 births.
  81. chondrocranium
    • endochondral cranial base
    • that later ossifies
    • • occipital, sphenoid, ethmoid, temporal (petrous part)
  82. desmocranium
    • intra)membranous bone to
    • the sides and tops of braincase; forms the
    • calvaria
    • • frontal, occipital, parietal
  83. viscerocranium
    • derived from pharyngeal
    • arches via membranous ossification. • temporal (squamous part), maxilla, zygomatic, mandible
  84. what does the brain form from and each part of the brain?
    • neural tube
    • forebrain> prosencephalon
    • midbrain>Mesencepahlon
    • hindbrain>rhombencephalon
  85. Craniosynostosis
    • deformity in the
    • cranium due to premature closure of
    • sutures. Type of defect depends on which
    • suture closes prematurely
  86. Microcephaly
    • caused by
    • abnormal development of the
    • brain, rather than premature
    • closure of sutures. Often
    • results in mental deficiency.
  87. Hydrocephalus? and frequency?
    • caused by
    • elevated pressure in
    • ventricles due to CSF
    • buildup. Occurs 1 in ~1,000
    • births.
  88. Pituitary Gland:
    • master gland for growth and reproduction 
    • pea-sized endocrine
    • gland that receives signal from the
    • brain via the hypothalamus and
    • produces hormones for the entire body
    • has anterior and posterior lobe that create diff hormones
  89. Anterior lobe formed from
    • upgrowth of ectodermal
    • roof of the mouth
    • (hypophyseal pouch)
  90. Posterior lobe formed from
    • downgrowth of floor of
    • diencephalon
    • (neurohypophyseal bud)
  91. the ectoderm germ layer contribute which part of the head and neck
    • brain & cranial nerves: from ectoderm-derived neural tube
    • • placodes: eye lens, vestibule, cochlea, nasal cavity
    • • parotid gland
  92. the mesoderm germ layer contribute which part of the head and neck
    • pharyngeal structures: in general from mesoderm but interacts
    • with ectoderm-derived neural crest cells. These include
    • branchiomeric muscles (e.g., extraocular mm, tongue, trapezius).
    • • skull: includes chondro-, desmo-, and viscerocranium
  93. the endoderm germ layer contribute which part of the head and neck
    • glands (except for parotid gland) & mucosae: interacts with
    • neural crest cells.
  94. where do NCC comes from
    • Ectoderm-derived but forms secondary mesenchyme
    • (mesectoderm) to form “mesoderm”-derived structures
  95. NCC migrate all over the body to turn into which structures ad is responsible for ?
    • Migrates all over the body to turn into cartilage and bone,
    • teeth, skin, melanocytes, smooth muscles, glands,
    • adipose tissue, neurons, glia, adrenal medulla, etc.
    • • Responsible for most of the connective and skeletal
    • tissue of the head, nerves, and pigment cells
  96. NCC contain information about how to
    develop specie specific structure and are able to recruit host tissue to schieve this
  97. NCC may ave a key factor in
    evolution of animals in entire body and ad skull
  98. the nervous system NCC derivatives ?
    sensory ganglia of CN V, VII, IX, X, and peripheral nerves
  99. the cartilage and bone  NCC derivatives ?
    • facial bones, some in the cranial base (parts of sphenoid bone),
    • middle ear ossicles (malleus, incus, stapes), hyoid, laryngeal
    • cartilage.
  100. the muscle NCC derivatives ?
Card Set
Week 12
Physiology, Pharmacology, DPR,OMM, and Anatomy of the head and neck