Neurobiology 1

Question 1

What does the CNS include?

Answer 1

brain and spinal cord

Question 2

What does the PNS include?

Answer 2

cranial nerves (attached to brain)
spinal nerves (attached to spinal cord)

Question 3

How does the PNS work?

Answer 3

transmits information from the sensory neurons (afferent signals) toward the brain, and away from the brain (efferent signals)

Question 4

What does the CNS arise from?

Answer 4

neural tube

Question 5

What does the PNS arise from?

Answer 5

neural crest cells

Question 6

How is the neural tube organization represented throughout life?

Answer 6

nervous tissue surrounds the interconnected series of ventricles (fluid filled channels)

Question 7

What is the signal between a neuron and another cell?

Answer 7

chemical signal via neurotransmitter (ex. acetylcholine)

Question 8

What type of signal is sent along a neuron?

Answer 8

electric impluse

Question 9

Grey matter

Answer 9

• lots of cell bodies

Question 10

White matter

Answer 10

• lots of axons

Question 11

Within the PNS where do cell bodies live?

Answer 11

• CNS or ganglia

Question 12

membrane potential and what is the resting one?

Answer 12

• difference in electrical charge between inside and outside of cell, NA-K pump puts 3 Na out and 2 K in making inside more negative at -70 mV

Question 13

ion channels

Answer 13

• allow passive flow ions along concentration gradients, when open
• can be specific for ion or for charge

Question 14

voltage gated ion channels

Answer 14

open in response to changes in voltage across membrane

Question 15

ligand gated ion channels

Answer 15

• open when bound to a specific molecule

Question 16

depolarization

Answer 16

when a channel opens and + charge ions move into the cell and negative charged ions move out of the cell and potential becomes more positive or vice versa

Question 17

synaptic cleft

Answer 17

between two neurons

Question 18

neurotransmitters

Answer 18

• excite: acetylcholine and glutamate
• inhibit: GABA and glycine

Question 19

astrocytes

Answer 19

• star shaped with many cellular processes
• provide support to tissue
• take up K+
• form a barrier around blood vessels to protect from circulating toxins
• store glycogen and make neurotransmitters

Question 20

oligodendrocites

Answer 20

• cellular processes wrap around neuronal axons form myelin (lipid rich) which insulates axons and increases action potential speed conduction
• can insulate up to 50 axons
• inhibit axon regeneration
• similar to schwann cells (PNS version)
• only in CNS

Question 21

schwann cells

Answer 21

• insulta axons in PNS
• 1:1 ratio
• facilitate regrowth of axons

Question 22

ependymal cells

Answer 22

• line fluid filled ventricular system
• can further specialize into choroid plexus cells and function in forming CSF

Question 23

microglia

Answer 23

• phagocytic cell of nervous system
• do not originate from neuroepithelial precursor cells