Pharyngeal Arches

Front 1

week during which gastrulation is complete

Back 1

week 3

Front 2

What kind of tissue is found at the core of each arch

Back 2

mesenchymal

Front 3

Core mesenchyme is made up of ______ mesoderm and ______mesoderm

Back 3

paraxial
lateral plate

Front 4

The lining of the core is made up to ___________

Back 4

epithelial derived endoderm

Front 5

Muscular components of the face and neck are derived from _________

Back 5

mesoderm

Front 6

skeletal components of the are derived from _______

Back 6

neural crest cells

Front 7

________ are the indentations between arches on the INTERnAL portion of the embryo.

________ are the indentation between arches on the EXTERNAL portion of the embryo

Back 7

Internal=pouches

external= clefts

Front 8

The first, second, and third pharyngeal arches develops by what week?

Back 8

4

Front 9

NC cells from the maxillary process differentiate into premaxilla, maxilla, zygomatic, and part of temporal bone via ___________ ossification

Back 9

Membrane

Front 10

Which arch is the mandibular process part of?

Back 10

Part of arch 1 (like the maxillary process)
Mandibular is from the VENTRAL portion of the first arch

Front 11

Which one grows larger--the mandibular process or the maxillary process?

Back 11

Mandibular

Front 12

Meckel's cartilage populates the _____________ process

Back 12

Mandibular

Front 13

Meckel's cartilage disintegrates by week ________, except for two small parts at the dorsal end of the first arch which become the _____ and ________

Back 13

week 8,
become the incus and malleus

Front 14

The incus and malleus (parts of the middle ear) are derived from which arch.

Back 14

1

Front 15

True of False

the mandible is derived from meckel's cartilage?

Back 15

False

It is derived from mesoderm that had surrounded Meckel's cartilage (before the cartilage disintegrated)

Front 16

the muscles of mastication (pterygoids, massetar, temporalis) are derived from which arch?

Back 16

1

Front 17

The anterior belly of the disgastric and the mylohyoid are derived from which arch?

Back 17

1

Front 18

The tensor tympani and tensor palatini are derived from which arch?

Back 18

1

Front 19

All the muscles derived from the first arch are innervated by ______?

Back 19

Mandibular branch of the trigeminal (CN 5, V3)

Front 20

Another name for the second arch?

Back 20

Hyoid arch

Front 21

Reichert's cartilage populates which arch ?

Back 21

2

Front 22

Stapes, styloid process, stylohyoid ligament, lesser horn and upper part of hyoid bone are derived from which arch?

Back 22

Hyoid arch

Front 23

Muscles of facial expression are derived from which arch?

Back 23

2

Front 24

The stapedius, stylohyoid, and posterior belly of digastric come from which arch?

Back 24

2

Front 25

the auricular muscle is from which arch

Back 25

2

Front 26

All muscles of the second arch are innervated by _______

Back 26

facial nerve

Front 27

The lower part of the hyoid bone and the greater horn of the hyoid bone are derived from arch _______

Back 27

3

Front 28

The only muscle that is derived from the third arch is the _______

Back 28

stylopharyngeus muscle

Front 29

The stylopharyngeus muscle is innervated by ________

Back 29

glossopharyngeal (CN 9)

Front 30

The 4th and 6th arches are visible by week ______

Back 30

5

Front 31

True or False

Cartilaginous components of the pharynx/larynx are derived from NC cells

Back 31

False. They come from the mesenchyme part of the arches

Front 32

The cartilage of the pharynx fuses to form which structures?

Back 32

Thyroid
cricoid
arytenoid
corniculate
cuneiform cartilage of larynx

Front 33

name the three muscles derived from the fourth arch?

Back 33

Cricothyroid
leavtopalatini
contrictors of the pharynx

Front 34

Derivatives of the 4th and 6th arch are innervated by the +__________

Back 34

Vagus (CN 10)

Front 35

All the intrinsic muscles of the larynx are innervated by the recurrent laryngeal branch of the vagus except for the _______ which is innervated by the _______ branch of the vagus

Back 35

Cricothyroid muscle, superior laryngeal branch)

Front 36

How many pharyngeal pouches are there?

Back 36

5 (5 internal indentations)

Front 37

The tubotympanic recess comes from pouch _______ and develops into the ________

Back 37

1, external auditory meatus, primitive tympanic (middle ear), eustachian tube

Front 38

Palatine tonsils comes from pouch _____

Back 38

2

Front 39

The inferior parathyroid gland comes from the ______ wing of pouch _______

Back 39

dorsal, 3

Front 40

The thymus comes from the _______ wing of pouch ______

Back 40

ventral, 3

Front 41

By week _____, the parathyroid gland and thymus lose their connection to the pharyngeal wall

Back 41

10

Front 42

The thymus migrates in which direction, pulling the inferior parathyroid with it

Back 42

Medially and caudally to fuse with its counterpart on the other side (at the midline of the neck)

Front 43

The superior parathyroid gland comes from the ______ wing of pouch ______

Back 43

dorsal, 4

Front 44

The superior parathyroid gland migrates along with the ____

Back 44

thyroid gland

Front 45

The ultimobrachial body, which is incorporated into the thyroid gland, comes from pouch _____

Back 45

5, sometimes considered part of 4

Front 46

What kind of cells are contained within the ultimobrachial body and what are those cells responsible for?

Back 46

C cells, secrete calcitonin, regulated blood calcium levels

Front 47

How many pharyngeal clefts are there?

Back 47

5

Front 48

Which cleft is the only one to contribute to a definitive structure/

Back 48

1

Front 49

The external auditory meatus is derived from?

Back 49

dorsal part of CLEFT 1

Front 50

The cervical sinus, which disappears, is formed by what event?

Back 50

second cleft growing over cleft 3,4, and 5, and merging with the epicardial ridge.

Front 51

If the second cleft fails to grown caudally over 3, and 4/5, what is the resulting defect?

Back 51

Branchial fistula,"", (sinuses that are open to the outside by a canal)

Front 52

NC cells are deficient in ______ and ________

Back 52

superoxide dismutase, catalase enzymes

These things help scavenge free radicals

Front 53

NC cells are vulnerable to these compounds.

Back 53

retinoic acid and alcohol

Front 54

What are the features of Treacher Collins Syndrome?

Back 54

malformed zygomatic bone
mandibular hypoplasia
lower eyelid colobomas
malformed external ears

Front 55

DiGeorge Sequence/syndrome is a defect of pouch(es) ______

Back 55

3 and 4

Front 56

DiGeorge syndrome is characterized by what?

Back 56

absence of thymus and parathryoid glands
abnormal external ears
hypertelorism (widely spaced eyes)
hypocalcemia
immunological problems

Front 57

How many rhombomeres are there

Back 57

8

Front 58

Arch 1 is populated by which rhombomere(s)

Back 58

R1 and R2

Front 59

Arch 2 is populated by which rhombomere(s)

Back 59

R4

Front 60

Arch 3 is populated by which rhombomere(s)

Back 60

R6 R7

Front 61

Arch 4 and 6 are populated by which rhombomere(s)

Back 61

R8

Front 62

Patterning of segments is controlled by ____ genes

Back 62

HOX

Front 63

HOX proteins are carried in _________ from the rhombomeres to the __________

Back 63

Carried in NC cells from the rhombomeres to the arches

Front 64

Shh is a regulator of _______

Back 64

HOX genes

Front 65

HOX genes are regulators of ______

Back 65

NC cells

Front 66

Knocking out Shh is mice leads to ____

Back 66

headless mice

Front 67

Retinoids are regulators of ______

Back 67

HOX genes

Front 68

HOX genes are regulated by _____ and _____

Back 68

Shh and retinoids

Front 69

Retinoids bind to ________ which then bind(s) to _______

Back 69

RAREs, which then bind to Promoter region of HOX genes

Front 70

OTX2 is a type of ______

Back 70

transcription factor

Front 71

OTX2 is a key regulator of ________

Back 71

the first ARCH

Front 72

OTX2 is expressed in NC cells of which part(s) of the brain?

Back 72

Forebrain
Midbrain