Nervous System Organisation

Question 0

What kind of nerves go from periphery to CNS?

Answer 0

Afferent (sensory)

Question 1

What kind of nerves go from CNS to periphery (PNS)?

Answer 1

Efferent (motor)

Question 2

What is the most coming NT for excitatory neurones?

Answer 2

Glutamate

Question 3

What is the most coming inhibitory NT?

Answer 3

GABA (gamma-amino butyric acid)

Question 4

What is an axon collateral?

Answer 4

Branches off axon (enable single neurone to communicate with many others)

Question 5

A collection of neuronal cell bodies in the CNS is called a…?

Answer 5

Nucleus

Question 6

A group of functionally related axons in the CNS is called a ….?

Answer 6

Tract

Question 7

A bundle of axons in the PNS is a…?

Answer 7

Nerve

Question 8

A collection of neuronal cell bodies in the PNS is a…?

Answer 8

Ganglion

Question 9

SOMATIC NS: efferent (motor) neurones

• Cell body located in CNS/PNS?
• Myelination of axons is?
• Neurotransmitter?

Answer 9

Cell body: CNS
Axons are HEAVILY myelinated
NT: Ach

Question 10

SOMATIC NS: afferent (sensory) neurones

• Cell body located in CNS/PNS?
• Myelination of axons is?
• Neurotransmitter?

Answer 10

Cell body in PNS
Axons are myelinated/unmyelinated
NT: Glutamate

Question 11

SYMPATHETIC NS: 
Ganglia close to...?
Preganglionic fibres?
Postganglionic fribres?
Postganglionic NT?

Answer 11

CNS
Short and myelinated
Long and branch extensively
NA

Question 12

PARASYMPATHETIC NS: 
Ganglia close to...?
Preganglionic fibres?
Postganglionic fribres?
Postganglionic NT?

Answer 12

Target
Long and myelinated
Short and branch minimally
Ach

Question 13

Myelinating glial cells of the PNS are?

Myelinating glial cells of the CNS are?

Answer 13

Schwann cells

Oligodendrocytes

Question 14

Supporting glia of:

• CNS is….?
• PNS is…?

Answer 14

• Astrocytes

* Satellite glia

Question 15

Microglia are…?

Answer 15

Scavengers
Immune cells of CNS
Phagocytose debris

Question 16

Golgi Type I neurones have ____ axons?

Golgi Type II neurone have ____ axons?

Answer 16

Golgi type I: LONG axons, extend to other parts of brain.

Golgi type II: SHORT axons, don’t extend beyond cell body (interneurones)

Question 17

What brain regions make up the FOREBRAIN?

Answer 17

Cerebrum
Thalamus
Hypothalamus

Question 18

What function does the MIDBRAIN have?

Answer 18

Process visual and auditory data
Reflexive somatic motor responses
Maintainence of consciousness

Question 19

What functions does the pons have?

Answer 19

Relays sensory info to thalamus and cerebellum

Subconscious somatic and visceral motor centres

Question 20

The PROSENCEPHALON divides into which secondary brain vesicles and which brain regions?

Answer 20

Telencephalon —> cerebrum

Diencephalon —> thalamus + hypothalamus

Question 21

The RHOMBENCEPHALON divides into which secondary brain vesicles and forms which brain regions?

Answer 21

Metencephalon —> cerebellum + pons

Myencephalon —> medulla oblongata

Question 22

Explain the function of these midbrain regions:

1. Substantia nigra
2. Superior colliculus
3. Periaqueductal grey matter
4. Red nucleus

Answer 22

1. DA containg, motor system
2. Receives visual input, focus eyes to attention
3. Pain and fear pathways
4. Motor control

Question 23

Explain the function of these hindbrain/brainstem regions:

1. Reticular formation
2. Raphe nuclei
3. Area postrema
4. Locus coeruleus

Answer 23

1. Alertness, CV function (HR)
2. Contains 5-HT
3. Chemoreceptor trigger zone
4. NA +ve cells

Question 24

Which is the innermost layer if ye meninges?

Answer 24

Pia matter

Question 25

What is the space between the Dura and Arachnoid matter called?

Answer 25

Subdural space

Question 26

The LATERAL ventricles are located in the____ and separated by the _______?

Answer 26

``` Cerebral hemisphere (one in each hem) Septum pellucidum ```

Question 27

Where is the THIRD ventricle located?

Answer 27

Diencephalon

Question 28

Which ventricle is continuous with the central canal of the spinal cord?

Answer 28

Fourth

Question 29

What connects the 3rd and 4th ventricles?

Answer 29

Cerebral aqueduct

Question 30

What 4 factors determine resting membrane potential?

Answer 30

1. -ve charged intracellular PROTEINS 2. Na/K pump (3 Na out, 2 K in) 3. K+ ions (electrical force IN, greater concentration grad force OUT) 4. Na+ ions (small inward force, electrical + conc)

Question 31

What is the "electrical potential difference that balances the ionic concentration gradient"?

Answer 31

Equilibrium potential (E ion)

Question 32

What is the ionic driving force?

Answer 32

Difference between membrane potential (Vm) and equilibrium potential (Eion). = Vm - Eion

Question 33

Why is GHK (Goldman-Hodgkin-Katz) eq use to calculate membrane potential, not Nernst eq?

Answer 33

GHK takes into account different ion permeabilities

Question 34

Where in neurone is an AP generated?

Answer 34

Axon hillock

Question 35

How long does one action potential last?

Answer 35

6 ms

Question 36

Which phases of AP are in the ABSOLUTE refractory period? Therefore, which phases = RELATIVE refractory period?

Answer 36

Depolarization and repolarization (the spike) Hyperpolarization

Question 37

The CNS is derived from which type of tissue?

Answer 37

Ectoderm

Question 38

The PNS is derived from what type of tissue?

Answer 38

Neural crest