Embryo

Question 0

What is segmentation?

Answer 0

Division of brain and spinal cord.

Question 1

What is mesencephalic flexure?

Answer 1

Bend between the first two parts of the brain in an embryo.

Question 2

What causes folding at the cranial end of the embryo?

Answer 2

Dramatic growth of the brain

Question 3

How many divisions are in the early brain and what are they called?

Answer 3

Three. Prosencephalon (forebrain), mesencephalon (midbrain), rhombencephalon (hindbrain).

Question 4

What does the cavity of the neural tube form?

Answer 4

The ventricles and central canal of the spinal cord

Question 5

When going from 3 to 5 brain vesicles, what are the 5 vesicles?

Answer 5

Telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon.

Question 6

What does the telencephalon form?

Answer 6

Cerebrum, from lateral ventricles.

Question 7

What does the diencephalon form?

Answer 7

Epithalamus, thalamus, hypothalamus.

Question 8

What does the mesencephalon form?

Answer 8

Cerebral peduncles, superior colliculi, inferior colliculi

Question 9

What forms from the metencephalon?

Answer 9

Pons and cerebellum

Question 10

What forms from the myelencephalon?

Answer 10

Medulla oblongata

Question 11

What connect the right and left alar (dorsal) plates? What connect the bilateral basal (ventral) plates?

Answer 11

The roof plate, the floor plate.

Question 12

What is the chemical that signals the ventral part of the neural tube? Dorsal part?

Answer 12

Sonic hedgehog, BMP4.

Question 13

What chemical does the notochord emit?

Answer 13

Sonic hedgehog (shh)

Question 14

What surrounds the central canal of the neural tube?

Answer 14

Undifferentiated neuroepithelial cells surrounding the central canal

Question 15

What are the different types of segmentation?

Answer 15

Longitudinal- brain from spinal cord. Cross sectional- define areas for gray matter (cell bodies of neurons) and white matter (axons).

Question 16

where is the white and gray matter located in the spinal cord? In the brain?

Answer 16

Spinal cord- white matter (on the outside), gray matter ( on the inside). Brain- white matter (inside), gray matter (outside).

Question 17

What does the early neural tube consist of?

Answer 17

Pseudostratified columnar (neuro) epithelium. Nuclei appear to be in multiple layers. High degree of mitotic activity. Cell division & maturation result in population of bipotential progenitor cells, which give rise to either neuronal or glial progenitor cells.

Question 18

What do bipotential progenitor cells in the neural tube lead to?

Answer 18

Either neuronal or glial progenitor cells.

Question 19

What do neuronal progenitor cells make? Glial progenitor cells?

Answer 19

Neuron. Neuroglia.

Question 20

What is the function of the neuron?

Answer 20

Transmit electrochemical signals.

Question 21

What is the function of neuroglia?

Answer 21

Supporting cells of the CNS. Insulate, nourish, support and protect neurons.

Question 22

What are ependymoblasts? Where are they located?

Answer 22

Cells in the innermost layer of the neural tube. These cells differentiate into ependyma.

Question 23

What do glial cells give rise to?

Answer 23

Oligodendrocytes, astrocytes, ependymal and special glial cells.

Question 24

Which zone gives rise to neurons and neuroglia?

Answer 24

Ventricular zone (most medial)

Question 25

What is in the intermediate mantle (cortical zone)?

Answer 25

Post-mitotic neurons and glioblasts, which will become the inner gray matter (contains neuronal cell bodies and neuroglia).

Question 26

What makes up the white matter (marginal zone)?

Answer 26

Neuronal processes that surround the developing gray matter

Question 27

What is in the dorsal plate of the spinal cord? Ventral plate?

Answer 27

Sensory input (afferent). Motor output (efferent)

Question 28

What are the neural crest derived tissues?

Answer 28

Melanocytes, dorsal root ganglia, spinal nerves, sympathetic ganglia.

Question 29

What are the neural crest migration pathways?

Answer 29

Lateral and medial pathways, which go on either side of the dermomyotome.

Question 30

What types of ganglia are formed by the neural crest?

Answer 30

Sensory (dorsal root) ganglia, motor (autonomic, sympathetic chain, parasympathetic)

Question 31

What is in the central nervous system?

Answer 31

White matter (myelinated axons in tracts), gray matter (neuronal cell bodies and neuroglia)

Question 32

What is a tract in the CNS?

Answer 32

Bundles of axons originating and ending in CNS

Question 33

What are neuronal cell bodies located in the CNS called?

Answer 33

Nuclei

Question 34

What makes up the peripheral nervous system?

Answer 34

12 cranial nerves, 31 spinal nerves, other nerves, nerve endings, and ganglia (cell bodies in PNS)

Question 35

What are the two parts of the PNS?

Answer 35

Somatic and autonomic nervous systems

Question 36

What is the somatic nervous system?

Answer 36

Actions carried out voluntarily, sensations are consciously received.

Question 37

What is the autonomic nervous system?

Answer 37

Actions carried out involuntarily, sensations aren't consciously perceived (maintains homeostasis)

Question 38

What are the four types of information to/from the spinal cord?

Answer 38

General somatic afferent, general somatic efferent, general visceral afferent, general visceral efferent

Question 39

What does a ventral root contain?

Answer 39

General visceral efferent and general somatic efferent (motor)

Question 40

What do dorsal rami go to?

Answer 40

Epaxial back muscles (deep back), muscle and skin also.

Question 41

What do ventral rami go to?

Answer 41

Hypaxial muscles, lateral and entrap body wall.

Question 42

What do afferent nerves do?

Answer 42

Carry signals from the peripheral to the CNS, via dorsal roots. Have receptors for touch, pressure, temperature, pain, proprioception

Question 43

What do efferent neurons do?

Answer 43

Carry impulses away from CNS to skeletal muscle

Question 44

Explain a dorsal rhizotomy and why it's performed.

Answer 44

Nerves separated and identified by electrical stimulation. Some sensory nerve fibers are then cut. Can do this for cerebral palsy or chronic pain (radiofrequency rhizotomy)

Question 45

What is the condition where a person can't feel pain?

Answer 45

Congenital insensitivity to pain (CIP). Rare, can be bc of voltage-gated Na+ channel (SCN9A) in dorsal root ganglia. Five different kinds have been identified.

Question 46

What are characteristics of the autonomic nervous system?

Answer 46

Involuntary and automatic, not consciously perceived, two neurons in path from CNS to effector, one neuron for somatic, the two neurons in the NSR preganglionic and postganglionic.

Question 47

What muscles do the autonomic nervous system affect efferently?

Answer 47

Smooth and cardiac muscle, also glands.

Question 48

What are the two branches of the ANS?

Answer 48

Parasympathetic and sympathetic