Development Of The Brain And Spinal Cord

Question 1

What is neurulation?

Answer 1

• Neuroectoderm overlying notochord thickens to form neural plate
• Neural plate margins rise into neural folds, converting plate into a neural groove
• Neural groove deepens, folds, turns in & forms a neural tube
- forerunner of brain & spinal cord (CNS) op

Question 2

Name neural inducing factors?

Answer 2

1. follistatin,
2. Noggin, Notch
3. Wnt-1
4. Sonic hedgehog
5. Dorsalin-1
6. BMPs

Question 3

Neuroectodermal cells from dorsal side of neural tube form?

Answer 3

1. craniofacial connective tissues
2. skin pigmented cells - melanocytes
3. adrenal medullae & chromaffin cells
4. contribute to aortic arch branches
5. outflow tract septum of heart
6. dorsal root ganglia & autonomic ganglia & Schwann cells
7. thyroid C cells

Question 4

Name the 3 primary brain vesicles?

Answer 4

1. Forebrain - prosencephalon
2. Midbrain - mesencephalon
3. Hindbrain - rhombencephalon

Question 5

Name the secondary brain vesicles of the prosencephalon?

Answer 5

1. Telencephalon
2. Diencephalon

Question 6

Name the adult derivatives of the prosencephalon?

Answer 6

1. Telencephalon - cerebral hemispheres, corpus striatum
2. Diencephalon - epithalamus, thalamus and hypothalamus, pineal gland

Question 7

Name the cavities of the prosencephalon?

Answer 7

1. Telencephalon - lateral ventricles
2. Diencephalon - third ventricle

Question 8

Name the secondary vesicles of the mesencephalon?

Answer 8

Mesencephalon

Question 9

Name the adult derivatives of the mesencephalon?

Answer 9

Corpora quadrigemina
Crus cerebri

Question 10

Name the cavities of the mesencephalon?

Answer 10

Cerebral aqueduct of Sylvius

Question 11

Name the secondary vesicles of the Rhombencephalon?

Answer 11

Metencephalon
Myelencephalon
Myelon

Question 12

Name the adult derivatives of the rhombencephalon?

Answer 12

1. Metencephalon - cerebellum and pons
2. Myelencephalon - medulla
3. Myelon - spinal cord

Question 13

Name the cavities of the rhombencephalon?

Answer 13

1. Metencephalon - fourth ventricle
2. Myelon - central canal

Question 14

What is a brain flexure?

Answer 14

Brain grows faster than head so the brain bends to form three flexures that determine
- shape of cranial end
- Expansion of NT : for secondary vesicles

Question 15

What are the 3 brain flexures?

Answer 15

1. Midbrain/cephalic flexure - head fold formation
2. Pontine flexure divides hindbrain: metencephalon
   (cranial) & myelencephalon (caudal)
3. Cervical flexure - between hindbrain & sc