69 Brain development (incomplete)

Question 1

During 4 weeks, what are the primary brain vesicles?

Answer 1

1. Forebrain = prosencephalon
2. Midbrain = Mesencephalon
3. Hindbrain = Rhombencephalon

Question 2

What are the secondary vesicles of forebrain? They will become?

Answer 2

1. Telecephalon: cerebral hemisphere

2. Diencephalon > thalamus etc

Question 3

What is the secondary vesicle of mesencephalon? It will become?

Answer 3

mesencephalon;

midbrain

Question 4

What are the secondary vesicles of hindbrain (rhombencephalon)? They will become?

Answer 4

1. Metencephalon > pons + cerebellum

2. Myelencephalon > medulla

Question 5

Lateral ventricles derived from which secondary brain vesicle?

Answer 5

Lateral ventricles derived from which secondary brain vesicle? Telencephalon

Question 6

Third ventricle derived from which secondary brain vesicle?

Answer 6

Diencephalon

Question 7

Aqueduct derived from which secondary brain vesicle?

Answer 7

mescenphalon

Question 8

Upper part of 4th ventricle derived from which secondary brain vesicle?

Answer 8

Metencephalon

Question 9

Lower part of 4th ventricle derived from which secondary brain vesicle?

Answer 9

Myelencephalon

Question 10

What is the midbrain flexure/ cephalic flexure?

Answer 10

4th-5th week, forebrain rotates ventrally and then posteriorly around midbrain region >under midbrain region.

Question 11

What is the cervical flexure?

Answer 11

Ventral flexion between hindbrain and spinal cord. (4th-8th week)

Question 12

What is pontine flexure of the brain?

Answer 12

Dorsal flexion at the hindbrain, dividing it into mesencephalon and myelencephalon

Deepening of pontine flexure folds the mesencephalon back onto myelencephalon.

5-8th week

Question 13

Which of the following is true about the development of the myelencephalon?

A. Ala plates lie medial to the basal plates
B. Neuroblasts of alar plates form afferent sensory nuclei
C. Neutroblasts of basal plates from efferent motor nuclei
D. Rostral part: some neuroblasts from alar places form the olivary nuclei
E. Caudally, neuroblasts from basal plates form gracile nuclei and caudate nuclei.

Answer 13

All except A

A: Alar plate is more lateral to basal plate

D:Neuroblasts from the alar plates migrate into the marginal zone and form
isolated areas of gray matter: gracile nuclei medially and cuneate nuclei laterally

Question 14

Divergence of lateral walls causes the stretching and thinning of the ___________. Neural lumen forms the ______________.

Answer 14

Ependymal roof;

lower part of 4th ventricle

Question 15

Vascular pia mater together with ependymal roof forms the?

Answer 15

Tele choroidea

Question 16

Tela choroidea invaginates into
4th ventricle & differentiates into
____________ to produce
cerebrospinal fluid.

Answer 16

choroid plexus

Question 17

Myelencephalon:
Basal plate (motor)
1. Medial somatic efferent group: neurons of _____ nerve?
2. Intermediate special visceral efferent group: Neurons of ____________ nerve?
3. Lateral group general visceral efferent group: motor neurons of?

Answer 17

1. CN 12
2. CN9,10
3. of CN10, CN9 that supple involuntary musculature of the respiratory tract, intestinal tract, hear

Question 18

Myelencephalon:
Alar plate (sensory)
1. Somatic afferent group (most lateral) ?
2. Special visceral afferent group (intermediate)?
3. General visceral afferent group?

Answer 18

1. 1 General somatic afferent group: receives general sensation from surface of head and neck and from mucosa of oral and nasal cavities and pharynx
2. 2 special somatic afferent: hearing and balancing
3. impulses from taste buds and tongue, palate, oropharynx and epiglottis
4. interoceptive information via CN10 from gastrointestinal tract and heart

Question 19

Of the metencephalon, specialization of the alar plate develops into?

Answer 19

cerebellum

Question 20

Some neuroblasts of the alar plate and the metecephalone form _________ nuclei, and migrate to ventral side

Answer 20

Pontine nuclei