W1 Disorders of transmission

Question 1

Types of neurons

Answer 1

multipolar – typical motor neuron
bipolar – typical special sensory neuron
unipolar – typical somatosensory neuron

Question 2

ganglia

Answer 2

• collections of cell bodies outside the CNS =

Question 3

nuclei

Answer 3

collections of cell bodies within the CNS

Question 4

Propagation of information by neurons

Answer 4

an Act Pot is a rapid, transient depolarisation of the cell membrane
* sodium channels in the membrane open and sodium flows into the cell, bringing positive electrical charge and so reducing the resting membrane
potential
* if the reduction of the resting membrane potential reaches threshold an AP will result

Question 5

what produces myelin

Answer 5

oligodendrocytes in CNS
Schwann cells in PNS

Question 6

what does myelin do

Answer 6

myelin wraps around the axon of a neuron and acts as s an insulator that increases the speed of conduction along the axon

Question 7

Events that result in synaptic
communication

Answer 7

1) AP reach presynaptic terminal
2) Ca+ enters presynaptic terminal through Ca+ voltated gated channel
3) Ca+ binds to docking protein
4) vesicles containing neurotransmiiter (NT) fuse w membrane and release NT
5) NT binds to postsynaptic receptor
6) membrane channels change shape and ions enter postsynaptic cell

Question 8

what are Neurotransmitters

Answer 8

Chemicals released from an axon terminal

Question 9

what are excitatory NT

Answer 9

– binding of the neurotransmitter causes depolarisation of the post-synaptic membrane, if the membrane reaches
threshold an AP will result

Question 10

what are inhibitory NT

Answer 10

binding of the neurotransmitter causes further polarisation of the post-synaptic membrane, moving the membrane away
from threshold and so reducing the chance of an AP occurring

Question 11

grey matter is

Answer 11

neuronal cell bodies and dendries

Question 12

white matter

Answer 12

axon and myelin