Embryology

Question 1

What is NTD

Answer 1

Neural tube defects

Question 2

NTDs tha affect the brain are called

Answer 2

Anencephaly

Encephalocele

Question 3

A NTD that affects the spinal cord is called

Answer 3

spina bifida

Question 4

What is anencephaly

Answer 4

failure of the upper part of the neural tube to close all the way.
Forebrain and cerebrum might be missing.
Remaining parts of brain often uncovered.

Question 5

What is encephhalocele

Answer 5

Failure of Neurulation.
Occurs early in pregnancy.
part of skull doe not close completely 
Causes part of brain to come through the open skull.
Can be located in:
Back of skull.> girls 
Front of skull.> boys 
Area of nose, sinuses and forehead
Top of skull.

Question 6

What is the name for a bulge that includes a pouch of brain and meninges.

Answer 6

meningoencephalocele.

Question 7

What is the name for a encephalocele that contains brain tissue as well as a ventricular cistern

Answer 7

meningohydroencephalocele

Question 8

What are three types of Spina Bifida

Answer 8

Myelomeningocele: Sac of fluid w part of spinal cord and nerves, they are usually damaged.
Meningocele: Sac of fluid, usually little or no nerve damage.
Spina bifida occulta: Small gap in the spine, w/o opening or sac on the back.

Question 9

What structures are in an arch

Answer 9

Nerve
Cartilage
Artery
Internal endodermal Pharyngeal pouch
External ectodermal pharyngeal cleft
Mesenchymal core of somatic mesoderm 
Neural crest mesenchyme

Question 10

How many pharyngeal arches are there

Answer 10

five

Question 11

How many pharyngeal pouches are there

Answer 11

four

Question 12

What comes from the first pouch

Answer 12

pharyngotympanic tube

Question 13

What comes from the second pouch

Answer 13

Tonsil

Question 14

What comes from the third pouch

Answer 14

Thymus and inferior parathyroid

Question 15

what comes from the fourth pouch

Answer 15

Superior parathyroid
Ultimobranchyal body
C-cells of the thyroid.

Question 16

What forms the outer pharyngeal clefts (grooves)

Answer 16

Ectoderm

Question 17

What forms from the cartilage of the first arch

Answer 17

Palatopterygoquadrate cartilage; maxilla and incus

Meckel’s cartilage; mandible and malleus

Question 18

What forms from the somatic mesoderm of the first arch

Answer 18

terminal branch of the maxillary artery.

Muscles of mastication: Masseter, temporalis and pterygoids.

Question 19

what forms from the cartilage of the second arch

Answer 19

Reichert's cartilage.
Stapes
Styloid process.
Styloid Hyoid ligament.
Lesser horns and upper rim of hyoid bone.

Question 20

What forms from the somatic mesoderm of the second arch

Answer 20

muscles of facial expression: orbicularis oculi, orbicularis oris, risorius, platysma, auricularis, fronto occypitalis, buccinator.
Posterior belly of digastric.
stylohioid

Question 21

What nerve innervates the second arch

Answer 21

facial nerve CN VII

Question 22

What nerve innervates the first arch

Answer 22

trigeminal nerve CN V

Question 23

if the lateral cervical sinus from the second arch persists what is the resuls

Answer 23

a cervical cyst anterior to the SCM muscle

Question 24

if a cervical cyst opens into the outside or the inside, it is via a

Answer 24

cervical fistula.

Internal fistula opens into the palatine tonsil.

Question 25

What forms from the cartilage of the third arch

Answer 25

Lower rim of hyoid bone. (body)

Greater horn of hyoid.

Question 26

What forms from the somatic mesoderm of the third arch

Answer 26

Stylopharyngeus muscle

Question 27

What two arteries are associated with the third arch

Answer 27

Common carotid artery

Internal carotid artery

Question 28

What nerve innervates the third arch

Answer 28

glossopharyngeal nerve CN IX

Question 29

What gives rise to the laryngeal cartilages

Answer 29

the lateral plate of the fourth and sixth arches

Question 30

What innervates the fourth arch

Answer 30

the superior laryngeal branch of the vagus nerve

Question 31

What innervates the sixth arch

Answer 31

the recurrent laryngeal branch of the vagus nerve

Question 32

The fourth arch gives rise to

Answer 32

Arch of the aorta,
right subclavian artery 
Original pulmonary arteries
Constrictors of the pharynx.
cricothyroid.
Levator veli palatine muscles

Question 33

The sixth arch gives rise to

Answer 33

Intrinsic muscles of the larynx

Question 34

First pharyngeal cleft develops into

Answer 34

External auditory canal.

Defects, develop into pre auricular cysts or fistulas

Question 35

The first pharyngeal pouch develops into

Answer 35

Eustacian tube

Middle ear cavity

Question 36

The second pharyngeal pouch develops into

Answer 36

Crypts of the palatine tonsil

Question 37

The third pharyngeal pouch develops into

Answer 37

Dorsal; Inferior parathyroid glands

Ventral; Thymus

Question 38

The fourth pharyngeal pouch develops into

Answer 38

Dorsal; superior parathyroid

Ventral; ultimobranchial body.

Question 39

Does the thyroid develop from any of the pouches

Answer 39

NO, it arises from a midline thyroid diverticulum

Question 40

What results from anomalies in thyroid development

Answer 40

Ectopic thryroid tissues and or cysts

Question 41

What syndrome is associated with anomalous dev of pouches 3 and 4

Answer 41

DiGeorge syndrome

deletion in the q arm of 22

Question 42

What is DiGeorge syndrome

Answer 42

hypoplasia of third and fourth pharyngeal pouch derivatives:
Ectopic or absent parathyroid, thymic or parafolicular thyroid tissue.
Heart defects (tetralogy of Fallot)
Hypoparathyrodism; low calcium and high Phosphorus in blood.
Cleft palate.
Small low set ears, wide-set eyes, long face, flattened groove in upper lip