Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuro B4 - WLB > Embryo of Head and Neck - Ach > Flashcards

Embryo of Head and Neck - Ach Flashcards

1
Q

What is the pharyngeal/brachial apparatus?

A
  • Bars of mesenchyme that surround the developing foregut and neural tube
    • five pair of arches
    • primitive pharynx
  • Covered externally with ectoderm
  • Lined internally with endoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a pharyngeal arch?

A
  • elevation that is separated from the next by a depression
    • five pair (1,2,3,4,6)
  • made up of 3 embryonic layers + neural crest cells
  • core = mesenchyme + own nerve/blood supply
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a pharyngeal pouch?

A

Depressions between arches on the inside of the pharyngeal gut

  • epithelial endoderm-lined
  • four pair
  • numbered rostral –> caudal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a pharyngeal cleft?

A

Depression between the arches on the outside (external) side of the pharyngeal gut tube.

  • covered with surface ectoderm
  • four pair
  • numbered rostral –> caudal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the pharyngeal membrane?

A
  • separate the pouches from the clefts
  • apposed layers of ectoderm and endoderm with intervening mesenchyme
  • this membrane does not break down in humans
    • so clefts and pouches do not normally communicate with one another (as they do in gills of fish)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the skeletal derivatives of the 1st pharyngeal arch?

A
  • Skeletal elements
    • Maxillary Prominence (intramembranous ossification):
      • maxilla
      • zygomatic bone
      • squamous part of temporal bone
    • Mandibular Prominence (Meckel’s cartilage)(endochondral)
      • incus
      • malleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the muscular derivatives of the 1st Pharyngeal arch?

A
  • Muscles of mastication:
    • Temporalis
    • Masseter
    • Pterygoids
  • Mylohyoid
  • Anterior belly of the digastric
  • Tensor tympani
  • Tensor veli palatini

(“Tense, tense, chew, chew!”)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are/is the neural derivatives of the 1st arch?

A

Trigeminal Nerve (CN V)

(SVE (branchial motor) fibers are found only in V3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the skeletal derivatives of the 2nd Pharyngeal Arch?

A
  • Reichert’s cartilage (endochondral ossification):
    • Stapes
    • Styloid process of temporal bone
    • Stylohyoid ligament
    • Lesser horn and upper body of hyoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the muscular derivatives of the 2nd Pharyngeal Arch?

A
  • Muscles of facial expression
  • Posterior belly of the digastric
  • Stylohyoid
  • Stapedius
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the neural derivatives of the 2nd Pharyngeal Arch?

A

Facial Nerve (CN VII)

  • SVE component
  • SVA component
    • Chorda tympani (taste from anterior 2/3 of tongue)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the skeletal derivatives of the 3rd Pharyngeal Arch?

A

Lower part of body and greater horn of hyoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the muscluar derivatives of the 3rd Pharyngeal Arch?

A

Stylopharyngeus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the neural derivatives of the 3rd Pharyngeal Arch?

A

Glossopharyngeal Nerve (CN IX)

(SVE - taste for posterior 1/3 of tongue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the skeletal derivatives of the 4th & 6th Pharyngeal Arches?

A
  • Laryngeal cartilages
    • Thyroid
    • Cricoid
    • Arytenoid
    • Corniculate
    • Cuneiform
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the muscular derivatives of the 4th Pharyngeal Arch?

A
  • Muscles of the soft palate (except tensor veli palatini)
  • Muscles of the pharynx (except stylopharyngeus)
  • Cricothyroid
  • Cricopharyngeus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the muscular derivatives of the 6th Pharyngeal Arch?

A
  • Intrinsic muscles of the larynx
  • Striated (upper) muscle of esophagus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the neural derivative of the 4th Pharyngeal Arch?

A

Vagus Nerve (CN X) - Superior Laryngeal Branch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the neural derivative of the 6th Pharyngeal Arch?

A

Vagus Nerve (CN X) - Recurrent Laryngeal Branch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What primitive structure gives rise to the tubotympanic recess and subsequent Auditory tube, Tympanic cavity, and Mastoid air cells?

A

First Pharyngeal Pouch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What primitive structure gives rise to the palatine tonsils?

A

Second Pharyngeal Pouch

22
Q

What primitive structure gives rise to the thymus and inferior parathyroid glands?

A

Third Pharyngeal Pouch

23
Q

What primitive structure gives rise to the Superior parathyroid glands and the Ultimobranchial bodies (parafollicular/C-cells of the thyroid gland)?

A

Fourth Pharyngeal Pouch

24
Q

What does the first pharyngeal cleft develop into?

A

External auditory meatus

25
Q

What primitive structure overgrows the 2nd, 3rd, and 4th pharyngeal clefts allowing for the disappearance of the cervical sinus and the external surface of the neck to become smooth?

A

2nd Pharyngeal Arch

26
Q

What two possible structures may persist is the cervical sinus does not disappear?

A

Lateral Cervical (branchial) Cyst OR Fistula

27
Q

What is the only pharyngeal membrane that contributes to an adult structure? What is the adult structure called?

A

First Pharyngeal Membrane => Tympanic Membrane

28
Q

The thyroid diverticulum evolves as a midline endodermal evagination from the floor of the pharynx between what two pharyngeal arches?

A

First & Second

29
Q

What adult structure in the tongue marks the site of the thyroid gland origin?

A

Foramen cecum

30
Q

When does the thyroid gland reach its position anterior to the trachea?

A

Week 7

31
Q

What primitive structures give rise to the tongue?

A

Mesenchyme from the first four pharyngeal arches

32
Q

What primitive structure gives rise to the epiglottis?

A

Midline swelling in the 4th Pharyngeal Arch

33
Q

What is the embryologic basis of First Arch Syndromes?

A
  • Disappearance of OR abnormal development in the first pharyngeal arch
  • Likely due to insufficient mesenchyme OR a deficiency of neural crest cells migrating into the first arch
34
Q

What are the two main forms of First Arch Syndrome?

A
  1. Treacher Collins Syndrome
  2. Pierre Robin Syndrome
35
Q

What specific First Arch Syndrome results in mandibulofacial dysostosis, hypoplasia of the zygomatic region and mandible, deformities of external/middle ear, conductive hearing loss, high or cleft palate, and defects of the lower eyelids (coloboma)?

A

Treacher Collins Syndrome

36
Q

What specific First Arch Syndrome results in extreme hypoplasia of the mandible (micrognathia), bilateral cleft palate, large posteriorly placed tongue that interferes with the airway, and defects of the ears?

A

Pierre Robin Syndrome

37
Q

What do you call an inferior pathathyroid gland that fails to descend, remains near the bifurcation of the carotid artery, and/or is found in the thorax with the thymus?

A

Accessory or Ectopic Parathyroid

38
Q

What do you call thymus that breaks off and is found either embedded in the thyroid gland, in association with the inferior parathyroid, or in isolated “nests”?

A

Accessory Thymus Tissue

39
Q

What disease/condition results in hypoplasia/abscence of the thymus and parathyroid glands, other problems involving the mouth/nose/ears/heart, loss of T-cell immunity, and tetany due to hypocalcemia?

A

DiGeorge Syndrome

40
Q

What disease/condition is associated with a microdeletion on q11 of chromosome 22?

A

DiGeorge Syndrome

41
Q

What disease/condition is due to improper migration of neural crest cells leading to failure of 3rd and 4th pouches to differentate plus hypoplasia of first arch derivatives?

A

DiGeorge Syndrome

42
Q

What congenital thyroid abnormalities may arise due to failures in development?

A
  • Thyroglossal cyst, duct, or fistula
    • remnant of thyroglossal duct
    • midline development of thyroid cartilage
  • Ectopic, aberrant, or accessory thyroid tissue may also be found anywhere along the path of the thyroglossal duct
    • may form a “lingual thyroid”
43
Q

What disease/condition results in low-set external ears, “Fishmouth” appearance, and is due to teratogenic causes or autosomal dominant genetic inheritance?

A

Treacher Collins Syndrome

44
Q

What disease/condition is a 1st and 2nd Arch Syndrome combination, results in hemifacial microsomia, and is though to be due to vascular insult etiology?

A

Goldenhar Syndrome

45
Q

What is the difference in appearance between a Branchial cyst and a Thyroglossal cyst?

A

Branchial cyst = Lateral

Thyroglossal cyst = Medial

46
Q

What are most of the tongue muscles derived from?

A

Myoblasts that migrate from the occipital myotomes with the Hypoglossal Nerve.

47
Q

What is Ankyloglossia?

A

Tongue remains attached to floor of the mouth.

Cannot stick out tongue or latch on to nipple when suckling.

48
Q

Where is the site of origin of the thyroid diverticulum?

A

Foramen cecum of tongue:

-endodermal evagination from the floor of the pharynx between the 1st and 2nd pouches

49
Q

What is the Thyroglossal duct?

A

Connects thyroid to tongue during development.

(Foramen Cecum –> Thyroid Gland)

50
Q

What two types of cells come together to make the Thyroid Gland? What are the precursors of each?

A

Follicular Cells + Parafollicular Cells => Thyroid Gland

Thyroid diverticulum –> Follicular cells

4th Pharyngeal Pouch –> Parafollicular cells

Neuro B4 - WLB (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions