Embryology

Question 1

Define encephalocele

Answer 1

A sac-like protrusion of the brain and the membranes that cover it through an opening in the skull

Question 2

Scaphocephaly

Answer 2

Early closure of sagittal suture

Question 3

Acrocephaly

Answer 3

Early closure of coronal suture

Question 4

Plagiocephaly

Answer 4

Early closure of coronal and lambdoid sutures on one side of the skull

Question 5

Name the first and 2nd pharyngeal arches

Answer 5

1:mandibular
2: hyoid

Question 6

List the innervation of the pharyngeal arches

Answer 6

First(mandibula)-trigeminal
Second(hyoid)-facial
Third-glossopharyngeal
Fourth and 6th- superior laryngeal branch of vagus and recurrent laryngeal branch of vagus.

Question 7

Pharyngeal cleft

Answer 7

Separates the pharyngeal arches externally

Question 8

Pahryngeal pouch

Answer 8

Separates pharyngeal arches internally

Question 9

What does the first pharyngeal cleft contribute to

Answer 9

Formation of external acoustic meatus

Question 10

What forms the malleus and incus

Answer 10

When the dorsal end of Meckel’s cartilage ossifies it forms basis if malleus and incus

Question 11

Where is stapes formed from

Answer 11

Reichert’s cartilage

Question 12

Derivatives of 1st pharyngeal pouch

Answer 12

Tubotympanic recess, auditory tube, middle ear cavity

Question 13

Derivatives of second pharyngeal pouch

Answer 13

Palatine tonsils

Question 14

Which structures is the face derived from

Answer 14

*fronto-nasal process
*1st pharyngeal pouch(mandibular)
-maxillary and mandibular processes

Question 15

Name the 5 primordia of the face

Answer 15

*single frontonasal
*2 maxillary prominences
*3 mandibular prominences

Question 16

Derivatives of 3rd pharyngeal pouch

Answer 16

Dorsal:inferior parathyroid gland
Ventral:thymus gland

Question 17

Ankyloglossia

Answer 17

Tongue tie

Question 18

Microglossia

Answer 18

Underdeveloped tongue

Question 19

Macroglossia

Answer 19

Enlarged tongue

Question 20

Macroglossia

Answer 20

Enlarged tongue

Question 21

Aglossia

Answer 21

Absence of a tongue

Question 22

What forms the cheek

Answer 22

Fusion of Maxillary and mandibular processes

Question 23

When is the external ear ear formed

Answer 23

Week 6

Question 24

Which sinuses develop after birth

Answer 24

Frontal and shenoidal

Question 25

Which sinuses develop in the fetal life

Answer 25

Maxillary and ant and post ethmoidal air cells

Question 26

What does the frontonasal prominence form

Answer 26

Forehead and bridge of nose
Frontal and nasal bones

Question 27

What does the maxillary prominence form

Answer 27

Most of the upper lip
Upper cheek regions
Maxilla, zygomatic bone and secondary palate

Question 28

Derivatives of mandibular prominences

Answer 28

Mandible
Lower lip
Chin
Lower cheek regions

Question 29

What forms the inter maxillary segment

Answer 29

Medial nasal prominences

Question 30

What does the intermaxillary segment give rise to

Answer 30

Philtrum
Premaxillary part of maxilla
Primary palate

Question 31

When does palatogenesis start and end

Answer 31

Begins 5th week ,ends 12th week

Question 32

What does the palate develop from

Answer 32

Primary and secondary palate