Brainscape's Knowledge GenomeTM

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


See full index

OCB > Branchial Arches > Flashcards

Branchial Arches Flashcards

1
Q

How many branchial arches are there?

A

5 (1,2,3,4,6)

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

Why is there no 5th branchial arch?

A

It fails to develop and doesn’t become anything.

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

When do the branchial arches appear?

A

Week 4-5.

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

What separates all of the branchial arches?

A

Separated by pouches on the inside and branchial clefts on the outside.

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

How does the palate form?

A

Primary palate forms from front-nasal process (medial-nasal process).
Secondary palate forms from palatal shelves of the maxillary process (1st pharyngeal arch) which fuse at the palatine raphe (midline).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What structures does the primary palate give rise to?

A

Incisors and bone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What structures does the secondary palate give rise to?

A
  • Hard palate (including maxilla and palatine bones).
  • Soft palate (including
    extrinsic muscles: tensor veli palatini, levator ve
    li palatini, palatoglossus, palatopharyngeus,
    musculus uvulae).
  • Teeth (canines to molars).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When do nasal processes fuse?

A

7th week

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

What happens if there are defects in the fusion of the fronto-nasal processes and palatal shelves of maxillary processes?

A

Cleft palate/lip

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the 1st branchial arch form?

A

Maxillary process and mandibular process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What nerve innervates the 1st branchial arch?

A

V3 of trigeminal (CN V)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where is the Meckel’s cartilage located?

A

In the mandible. Mostly disappears except the incus and the malleus (of the middle ear).

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

What muscles are formed from the 1st branchial arch?

A

Muscles of mastication.

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

What can arise from abnormalities in the 1st branchial arch?

A

Treacher Collins Syndrome (underdeveloped face).

Pierre Robin Sequence (underdeveloped mandible, cleft palate).

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

What does the 2nd branchial arch form?

A

Hyoid arch:

  • Stapes.
  • Styloid process.
  • Upper part of hyoid bone.
  • Lesser cornu.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What nerve innervates the 2nd branchial arch?

A

CN VII - facial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What muscles are formed from the 2nd branchial arch?

A

Muscles of facial expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does the cartilage of the 3rd branchial arch form?

A
  • Greater cornu.

- Lower part of hyoid bone.

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

What muscles are formed from the 3rd branchial arch?

A

Stylopharyngeus muscle

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

What nerve innervates the 3rd branchial arch?

A

CN IX - glosspharyngeal

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

What does the cartilage of the 4th branchial arch form?

A

Laryngeal cartilages, e.g. thyroid.

22
Q

What muscles are formed from the 4th branchial arch?

A

Pharyngeal constrictor muscles (inferior, superior, middle).

23
Q

What nerve innervates the 4th branchial arch?

A

CN X - vagus (superior laryngeal branch)

24
Q

What does the cartilage of the 6th branchial arch form?

A

Laryngeal cartilages, e.g. cricoid.

25
Q

What muscles are formed from the 6th branchial arch?

A

Intrinsic laryngeal muscles.

26
Q

What nerve innervates the 6th branchial arch?

A

CN X - vagus (recurrent laryngeal branch)

27
Q

What lines the brachial clefts?

A

Ectoderm

28
Q

Which branchial cleft forms a structure in the adult?

A

1st branchial cleft.

29
Q

Where is the 1st branchial cleft located?

A

Between the 1st and 2nd branchial arches.

30
Q

What does the 1st branchial cleft form?

A

External auditory canal/meatus.

31
Q

What is the meatal plug?

A

Epithelial plate of cells formed by the ectoderm at the bottom of the cleft at month 3.

32
Q

Why is there only 1 branchial cleft?

A

The mesenchyme from the 2nd arch expands and fuses with the 6th arch, blocking off other clefts. Therefore, all other clefts obliterate during development.

33
Q

What happens if there is incomplete fusion of the 2nd and 6th branchial arch?

A

Branchial sinus (small hole in the neck).

34
Q

What are the consequences of a branchial sinus?

A

Formation of cysts or fistulas which can damage the facial nerve.

35
Q

What lines branchial pouches?

A

Endoderm.

36
Q

What does the 1st branchial pouch form?

A

Tubotympanic recess

37
Q

What does the 2nd branchial pouch form?

A

Palatine tonsils

38
Q

What does the 3rd branchial pouch form?

A

Inferior parathyroid gland and thymus.

39
Q

What does the 4th branchial pouch form?

A

Superior parathyroid glands.

40
Q

What does the 5th branchial pouch form?

A

Ultimobranchial body (incorporated into thyroid).

41
Q

Which duct is commonly lost?

A

Thyroglossal duct.

42
Q

What happens if the Thyroglossal duct remains?

A

It can cause a thyroglossal cyst.

43
Q

What is connected by the Thyroglossal duct?

A

The developing thyroid gland to the wall.

44
Q

What does the distal portion of the 1st branchial pouch form?

A

Primitive tympanic cavity (middle ear)

45
Q

What does the proximal region of the 1st branchial pouch form?

A

Eustachian tube.

46
Q

Which branchial arches are involved in tongue development?

A

1st arch - anterior 2/3 tongue

3rd and 4th arch - posterior 1/3 of tongue

47
Q

Which cells give rise to tongue muscles?

A

Myogenic cells (when they migrate from the occipital somite via the hypoglossal chord).

48
Q

Where do the tongue muscles originate from?

A

Mesoderm and occipital somites.

49
Q

What is a somite?

A

Body region formed during development.

It forms segmented vertebrae and associated tendons/muscles.

50
Q

What is ankyloglossia?

A

Tongue tie.

51
Q

What causes ankyloglossia?

A

Mesenchyme failing to regress so tongue is attached to floor of mouth.

OCB (8 decks)

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