M2-C2-L45 --> Head And Neck Development

Front 1

The face is formed from what?

Back 1

Neurocranium

Viscerocranium

Front 2

The maxilla and mandible arise from which pharyngeal arch?

Back 2

1st

Front 3

What does the stomaduem become?

Back 3

Oral cavity

Front 4

Describe what cranial neural crest cells do in development.

Back 4

They migrate into head, neck, and pharyngeal arch mesoderm in three streams.

Each stream differentiates into:
- Cranial Nerve Ganglion
- Mesenchyme

These form into skeletal and connective tissue characteristic of that arch.

Front 5

What are the major playas in stimulating proliferation of Neural Crest cells in the area?

Back 5

Sonic Hedgehog

FGF8

Front 6

Front of skull (including face) is derived from where?

Back 6

Mesenchyme from Neural Crest

Front 7

Posterior skull is derived from where?

Back 7

Paraxial Mesoderm

Front 8

Carotid artery comes from what embryological artery?

Back 8

Arteries of Pharyngeal arch #3

Front 9

The Right Subclavian artery comes from what embryological artery?

Back 9

Right artery of Pharyngeal arch #4

Front 10

The Pulmonary artery comes from what embryological artery?

Back 10

The Right artery of Pharyngeal arch #6

Front 11

The Aorta comes from what embryological artery?

Back 11

The Left artery of Pharyngeal arch #4.

Front 12

The Ductus Arteriosus comes from what embryological artery?

Back 12

The Left artery of Pharyngeal arch #6

Front 13

Describe the formation of the Aorta.

Back 13

The superior half of the Truncus Arteriosus will break off, while the attached artery of pharyngeal arch #4 thickens.

Front 14

Describe the formation of the Pulmonary trunk.

Back 14

Lower part of the Truncus Arteriosus will detach from the aorta.

Front 15

Describe the development of the vagus nerve in embryological events.

Back 15

Recurrent laryngeal branch of Vagus loops around 6th aortic arch artery.

On the RIGHT side, the 6th aortic arch artery will regress,

causing the pharyngeal nerve to ascend and loop around the 4th Arch artery (subclavian)

Front 16

List the cranial nerves.

Back 16

Trigeminal (V)
Facial (VII)
Glossopharyngeal (IX)
Vagus (X)

Front 17

Define SVE

Back 17

Axons of lower motor neurons which innervate skeletal muscles derived from the Pharyngeal arches.

Front 18

How can six pharyngeal arches become four Cranial nerves?

Back 18

1st becomes V
2nd becomes VII
3rd becomes IX

4th and 6th combine to become X

5th is vestigial

Front 19

What are the cartilages associated with the pharyngeal arches?

Back 19

1st - Meckel's

2nd - Reichert's

3rd - Hyoid bone

4th and 6th - Larynx

Front 20

Describe the structures developed from Meckel's cartilage?

Back 20

Mandible

Maxilla

Malleus

Incus

Front 21

Describe the structures developed from Reichert's cartilage.

Back 21

Stapes

Styloid process

Stylohyoid ligament

Lesser horn of hyoid

Front 22

Describe the structures developed from hyoid bone (cartilage of 3rd arch)

Back 22

Greater horn of hyoid

Body of hyoid

Front 23

Describe the structures developed from the cartilage of the 4th arch.

Back 23

Thyroid

Front 24

Describe the structures developed from the cartilage of the 6th arch.

Back 24

Cricoid

Front 25

Describe the development of neural crest cells to muscle.

Back 25

They are not involved, you homo

Front 26

List the muscles developed from the 1st pharyngeal arch.

Back 26

Temporalis
Masseter
Pterygoids (medial & lateral)

Mylohyoid
Anterior Belly of Digastric
Tensor Tympani
Tensor Veli Palatini

Front 27

List the muscles developed from the 2nd pharyngeal arch.

Back 27

Muscles of facial expression
Posterior Belly of Digastric
Stylohyoid
Stapedius

Front 28

List the muscles developed from the 3rd pharyngeal arch.

Back 28

Stylopharyngeus

Front 29

List the muscles developed from the 4th pharyngeal arch.

Back 29

Muscles of:
- pharynx
- larynx
- soft palate

Except for:
- stylopharyngeus
- tensor veli palatini

Front 30

All skeletal muscles derived entirely from?

Back 30

Mesoderm

Front 31

Describe the formation of the internal ear.

Back 31

Ectoderm
induced by the notocord,

then the paraxial mesoderm

results in formation of
Otic Placode

This becomes Otic vesicle

which becomes the internal ear and its structures

Front 32

Describe what forms the middle and external ear.

Back 32

Develops from:
- pharyngeal pouch 1
- pharyngeal cleft 1

Front 33

What is the tympanic membrane made from?

Back 33

Ectoderm
Mesoderm
Endoderm

Front 34

The auricle is derived from what?

Back 34

Pharyngeal arch 1 (anterior) and arch 2 (posterior)

Front 35

What does the Rubella infection do to ear?

Back 35

During weeks 7 & 8,

will cause defects in inner ear (organ of corti)

Thus will result in permanent congenital deafness.

Front 36

Describe the innervation of the auricle.

Back 36

Anterior portion -> Trigeminal

Posterior portion -> Cervical plexus (C1 to C4)

Front 37

Most pharyngeal arch defects are caused by what?

Back 37

Insufficient amounts of Neural crest cells and other multifactorial factors.

Front 38

Describe Treacher-Collins Syndrome.

- Etiology
- Affects which part?
- Symptoms

Back 38

Autosomal Dominant

1st Arch syndrome

Mandible and facial hypoplasia

Malformation of ears

Cleft Palate

Faulty dentition

Front 39

Describe Agnathia

- Etiology
- Affects which part
- Symptoms

Back 39

Congenital defect

1st Arch syndrome

Failure of lower jaw to form

Failure of external ears to migrate to neck region.

Front 40

What does pharyngeal pouch #1 develop into?

Back 40

Auditory tube (endoderm)

Middle Ear Cavity (endoderm)

Front 41

What does pharyngeal pouch #2 develop into?

Back 41

Tonsillar Epithelium (endoderm)

Front 42

What does the pharyngeal pouch #3 develop into?

Back 42

Thymus

Inferior Parathyroid gland

Front 43

What does the pharyngeal pouch #4 develop into?

Back 43

Ultimobranchial body

Superior Parathyroid

Front 44

Describe DiGeorge Syndrome

- Etiology
- Affects which part?
- symptoms

Back 44

Congenital - chromosome 22 del.

Pharyngeal arches 3 and 4 fail to completely differentiate

Partial or fully incomplete thymus and parathyroids

Causing immunodeficiency and hypocalcemia

Front 45

What forms the Anterior Pituitary?

Back 45

Rathke's Pouch

Neuroectoderm of Hypothalamus