Embryology Lecture 1/27 from teriyaki sauce

Question 1

3 primary embryonic brain sections

Answer 1

Forebrain- Prosencephalon
Midbrain- Mesencephalon
Hindbrain- Rhombencephalon

Question 2

Neural Tube differentiates into the (broad answer)

Answer 2

Brain and Spinal Cord

Question 3

Neural Crest differentiates into the

Answer 3

Peripheral Nervous system and many non-neural derivatives

Question 4

Neural Canal differentiates into the

Answer 4

Ventricular System which further differentiates into the ventricles of the brain and the Central Canal of Spinal Cord

Question 5

Sulcus limitans

Answer 5

divides the Alar and Basal plates in the neural tube

Question 6

3 differentiating cell zones in neural tube (during week 4)

Answer 6

Ventricular Zone
Intermediate Zone
Marginal Zone

Question 7

Ventricular Zone

Answer 7

against the internal limiting membrane
has dividing neuroepithelial cells
turns into: Neurons & Glial Cells, Ependyma

Question 8

Intermediate Zone

Answer 8

is between ventricular and intermediate zones
has neuroblasts
turns into: Gray Matter

Question 9

Marginal Zone

Answer 9

against the external limiting membrane

turns into: white matter

Question 10

cells in the aral plate turn into

Answer 10

Secondary sensory neurons
Do not leave the CNS
synapse in gray matter or ascended in white matter as tract
make dorsal horn

Question 11

cells in the basal plate turn into

Answer 11

motor neurons
cell bodies stay in neural tube and axons grow out through the ventral root and exit the neural tube
make ventral and lateral horn

Question 12

The intermediate layer of the neural tube turns into these two plates

Answer 12

The Aral and Basal Plates

Question 13

Dorsal Root ganglia have sensory neurons that are derived from the

Answer 13

neural crest

Question 14

sensory neurons are pseudounipolar or unipolar but start out as

Answer 14

bipolar cells

Question 15

Process of Myelination (CNS vs PNS)

When does it start and end

Answer 15

CNS- done by oligodendrocyte
PNS- Schwann Cells
starts at 4th month
goes through 1st year after birth

Question 16

Babinski Sign

Answer 16

Corticospinal pathway not fully myelinated (slows signal) so primitive reflex is not blocked by cerebral cortex.

Causes fanning of toes instead of flexion.

Question 17

Forebrain (Prosencephalon) (primary structure) differentiates into

Answer 17

Telencephalon (Secondary Structure)—>Cerebral Cortex, Corpus Striatum, Olfactory Bulbs (Terminal Structures)

Diencephalon (Secondary Structure)—> Thalamus, Hypothalamus, Epithalamus, Subthalamus (Terminal Structures)

Question 18

Midbrain (Mesencephalon) (primary structure) differentiates into

Answer 18

Mesencephalon (Secondary Structure)—->Tectum, Tegmentum, Cerebral Peduncules (Terminal Structures)

Question 19

Hindbrain (Rhombencephalon) (primary structure) differentiates into

Answer 19

Metencephalon (Secondary Structure)—->Pons, Cerebellum (Terminal Structures)

Myelencephalon (Secondary Structure)—>Medulla (Terminal Structures)

Question 20

Caudal Neural Tube (Primary Structure) differentiates into the

Answer 20

Spinal Cord (Terminal Structures)

Question 21

Craniorachischisis

Answer 21

Failure of a large part of the neural tube to close. Neural tissue is exposed to amniotic fluid. This is bad. You will die.

Question 22

Anencephaly and Meroanencephaly

Answer 22

Failure of the Rostral Neuropore to close

Question 23

Spina Bifida

Answer 23

Posterior Neural Tube defect
Failure of the Caudal Neuropore to close
Problem of Induction

Question 24

Occipital Encephalocele

Answer 24

Anterior Neural tube defect

Brain and meninges protrude through occipital bone

Question 25

Syringomyelia

Answer 25

Not a neural tube defect
Tubular cavitation in the spinal cord
lose sense of pain and temperature in shoulders and upper arms

Question 26

Holoprosencephaly

Answer 26

Not a neural tube defect

The forebrain does not divide into two hemispheres

Question 27

Hydrocephalus

Answer 27

Not a neural tube defect
Dilation of the ventricles due to:
overproduction of CSF, obstruction of flow, or problem with reabsorption of CSF

Question 28

Dandy-Walker Malformation

Answer 28

Partial or Complete absence of cerebellar vermis

Question 29

Hirschsprung disease

Answer 29

failure of neural crest cells to migrate into the colon
no sympathetic neurons so no peristalsis
ballooning of colon with fecal retention