HD2 Anatomy2 Embryology Part 2

Question 1

The pharngeal arches are a series of outpuches of mesoderm on both sides of the developing WHAT? [1]

Answer 1

Pharynx

Question 2

The pharngeal arches are derived from which germ layers? [1]

Answer 2

All

Question 3

COme back and put in cross section stuff

Question 4

Laryngeal cartilage derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 4

Laryngeal cartilage derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 5

Anterior belly of digastric derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 5

Anterior belly of digastric derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 6

CN IX derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 6

CN IX derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 7

Mandible derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 7

Mandible derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 8

Maxilla derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 8

Maxilla derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 9

Stylopharngeus derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 9

Stylopharngeus derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 10

CN V derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 10

CN V derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 11

CN X derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 11

CN X derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 12

Posterior belly of digastric:
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 12

Posterior belly of digastric:
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 13

Muscles of facial expression:
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 13

Muscles of facial expression:
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 14

CN VII
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 14

CN VII
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 15

Muscles of pharynx (except stylopharyngeus)
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 15

Muscles of pharynx (except stylopharyngeus)
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 16

Muscles of mastication
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Answer 16

Muscles of mastication
derived from:

Arch 1
Arch 2
Arch 3
Arch 4

Question 17

What does the 1st pharyngel cleft form?

Internal auditory meatus

External auditory meatus

Meckel’s cartilage

Portion of maxillary artery

Answer 17

What does the 1st pharyngel cleft form?

Internal auditory meatus

External auditory meatus

Meckel’s cartilage

Portion of maxillary artery

Question 18

Reichert’s cartilage is the embryonic precusor to the stapes, styloid process, stylohyoid ligament and part of the hyoid bone. Which pharyngeal arch gives rise to Reichert’s cartilage?

1st

2nd

3rd

4th

Answer 18

Reichert’s cartilage is the embryonic precusor to the stapes, styloid process, stylohyoid ligament and part of the hyoid bone. Which pharyngeal arch gives rise to Reichert’s cartilage?

1st

2nd

3rd

4th

Question 19

Which of the following is NOT associated with the 4th pharyngeal arch?

Aortic arch

Laryngeal cartilages

Superior laryngeal nerve

Recurrent laryngeal nerve

Answer 19

Which of the following is NOT associated with the 4th pharyngeal arch?

Aortic arch

Laryngeal cartilages

Superior laryngeal nerve

Recurrent laryngeal nerve

Question 20

More photo qs

Question 21

What structures are derived from the 4 pharyngeal pouches?

Parathyroid glands, tonsilsm, thymus

Eyes

Nasolacrimal duct

Digastric

Answer 21

What structures are derived from the 4 pharyngeal pouches?

Parathyroid glands, tonsilsm, thymus

Eyes

Nasolacrimal duct

Digastric

Question 22

Development of the Thyroid Gland:

In the midline of the floor of the pharynx (tongue), the endodermal lining of the foregut forms the []

The [] (same as above) migrates caudally (downwards), passing anteriorly to the hyoid bone and laryngeal cartilages. During this migration, the thyroid remains connected to the tongue by the [], which later obliterates.

Answer 22

In the midline of the floor of the pharynx (tongue), the endodermal lining of the foregut forms the thyroid diverticulum.

The thyroid diverticulum migrates caudally (downwards), passing anteriorly to the hyoid bone and laryngeal cartilages. During this migration, the thyroid remains connected to the tongue by the thyroglossal duct, which later obliterates.

Question 23

When cells are left over in the thyroglossual duct before it closes, they can manifest as a []’, which is a small lump that remains.

Answer 23

When cells are left over in the duct before it closes, they can manifest as a ‘Thyroglossal Cyst’, which is a small lump that remains.

Add photo of possible cyst locations

Question 24

A 18 year old patient presents with a midline swelling in their neck, close to their hyoid bone. You suspect they have a thyroglossal duct.

How would you expect the lump to move when they stick their tongue out?

Elevate
Not Move
Depress

Answer 24

A 18 year old patient presents with a midline swelling in their neck, close to their hyoid bone. You suspect they have a thyroglossal duct.

How would you expect the lump to move when they stick their tongue out?

Elevate
Not Move
Depress

As the cyst is attached to the tongue it will move with the tongue. Protrusion of the tongue will pull the cyst up in the neck.

Question 25

State the area / structure of the tongue with the correct pharyngeal arch it is derived from. [3] Anterior 2/3 Epiglottis Posterior 1/3

Answer 25

Anterior 2/3rd: **Arch 1** Posterior 2/3rd: **Arch 3** Epiglottis: **Arch 4**

Question 26

Development of the face: The face is formed by which 3 swellings?

Answer 26

The frontonasal prominence The maxillary prominence (pharyngeal arch 1) The mandibular prominence (pharyngeal arch 1)

Question 27

What are nasal placodes? [1] Nasal placodes develop on the ventrolateral aspects of which facial swelling? [1] How do the nasal placodes develop and what do they form? [2]

Answer 27

**nasal placodes**: Bilateral ectodermal thickenings **Nasal placodes** develop on ventrolateral aspects of the **frontonasal prominence** **Invaginate** into the underlying **mesoderm** to form the **nasal pits**, thereby producing rides of tissue that from the **medial nasal prominence and the lateral nasal prominence** | Add photo

Question 28

Development of the Palate: What / where is the intermaxillary segment? [1]

Answer 28

The intermaxillary segment (primary palate) is the initial portion of the palate to develop. **It contains the central and lateral incisors.**

Question 29

A cleft lip is formed from the failure of which two structures to form? [2]

Answer 29

**Medial nasal prominence** **Maxillary prominence**

Question 30

Development of the Palate: Describe the intermaxillary palate forms

Answer 30

**Medial** **growth** of the **maxillary prominence** pushes the **two medial nasal prominences** together at the midline

Question 31

The secondary palate forms from which structures? [1]

Answer 31

The secondary palate forms from outgrowth of the maxillary prominences called the **palatine shelves.**

Question 32

Describe the process of secondary palate formation [2]

Answer 32

Initially: palatine shelves project downward on either side of the tongue Later: **palatine shelves move horizontally** and fuse along the **palatine raphe** to form the secondary palate

Question 33

PAWhere do the primary and secondary palatine fuse? [1] What structure does this form? [1]

Answer 33

The primary and secondary palate fuse at the **incisive foramen** to form the **definite palate**