Cellular Organisation of NS

Question 1

Cytoskeleton

Answer 1

Microtubules made of tubulin, microfilaments made of actin and neurofilaments make up core of axon. Microtubules provide a transport system that allows organelles and other molecules to be transported along the axon from cell body.

Question 2

Synaptic potentials are

Answer 2

graded potentials

Question 3

Compartmental models

Answer 3

3D models of dendritic trees and information about membrane properties that determine decay rates of graded potentials

Question 4

Axon hillock

Answer 4

Where activation is summed to illicit an a.p. if threshold is met

Question 5

Neurocircuit

Answer 5

Multiple neurons and neuro types are interconnected and working together to perform specific functions

Question 6

Types of channels

Answer 6

1. Mechanical
2. Ligand-gated
3. Voltage-gated
4. NT- gated

Question 7

Outline GPCR function

Answer 7

Signalling molecule docks to receptor which causes transformation of a transmembrane protein, triggering a second messenger cascade

Question 8

Dermatome

Answer 8

Area of skin innvervated by spinal cord

Question 9

Myotome

Answer 9

Multiple muscles innvervated by motor nerves -> most muscles are innvervated by 2 nerves

Question 10

How is the sympathetic NS organised?

Answer 10

1. Motor neurons from SC enter sympathetic ganglia -> synapse onto and excite large network of ganglionic motor neurons -> innervate viscera
2. Pass through sympathetic NS and activate other motor neurons closer to target tissue
3. Stimulate adrenal medullla -> adrenalin release

Question 11

Sympathetic NS functions

Answer 11

During stress, increases HR, vasoconstriction, dilation of blood vessels in muscle, slow down gut activity

Question 12

Parasympathetic NS functions

Answer 12

Digestion + bladder control

Question 13

How is the parasympathetic NS organised?

Answer 13

1. Parasympathetic pre-ganglion neurons come from brain stem and sacral SC -> effector neurons
2. Not clustered in ganglia -> ganglion neuron on surface of visceral organs

Question 14

Enteric NS function

Answer 14

Coordinates the secretion + muscle activity of G.I. system with input from G.I. and autonomic systems

Question 15

Thalamus

Answer 15

Gateway to cortex, integration of sensory, motor and autonomic information

Question 16

Cerebellum

Answer 16

Co-ordination and control of complex movement, balance, posture, hand-eye coordination

Question 17

Hippocampus

Answer 17

Learning and Memory

Question 18

Cortex

Answer 18

Analyse sensory input and compare with memory to generate understanding and complex behaviours -> higher mental functions e.g. reasoning, language, speech

Question 19

5 main cell types in cerebellum

Answer 19

1. Purkinje cells
2. Granule cells
3. Stellate cells
4. Basket cells
5. Golgi cells

Question 20

Amygdala

Answer 20

Emotional response

Question 21

4 major subdivisions of hippocampus

Answer 21

1. Dentate gyrus
2. Ca region
3. subiculum
4. entorhinal cortex

Question 22

Perforant pathway

Answer 22

Entorhinal cortex -> dentate gyrus -> CA3 -> CA1 -> subiculum

Question 23

Layer 3 of cortex

Answer 23

Large pyramidal cells that connect to other cortical areas

Question 24

Layer 4 of cortex

Answer 24

Main input layer for sensory inputs from the thalamus

Question 25

Layer 5 of cortex

Answer 25

Large pyramidal cells which axons project out of cortex to striatum and SC

Question 26

Layer 6 of cortex

Answer 26

Part of feedback loop that regulates incoming thalamic activity

Question 27

Spinothalamic pathway

Answer 27

pain + temperature

Question 28

Dorsal column pathway

Answer 28

touch/ proprioception to somatosensory cortex

Question 29

White matter consists of

Answer 29

Spinothalamic pathway, dorsal column pathway and 1 descending motor pathway