Control of Movement

Question 1

What is myasthenia gravis?

Answer 1

Autoimmune disease where antibodies destroy Ach receptors

Question 2

What are the signs of myasthenia gravis?

Answer 2

Weakness, tiredness, actions such as chewing more difficult

Question 3

What do myasthenia gravis affect?

Answer 3

NMJ

Question 4

What is a Neuromuscular junction?

Answer 4

Chemical synapse between a motor neurone and muscle fibre

Question 5

What is the stretch reflex?

Answer 5

Monosynaptic reflex, that muscle contracts if stretched

Question 6

Describe the stretch reflex

Answer 6

1) Muscle stretched, IF fibres stimulated
2) Afferent along 1a neurones to alpha motor neurone
3) Efferent impulse to EF fibre so contracts

Question 7

Describe the withdrawal reflex

Answer 7

1) Limb withdrawn from noxious stimuli
2) Afferent fibres synapse on MN in SC
3) Causes ipsilateral flexion and contralateral extension

Question 8

What 3 things ensure the smoothness and coordination of movement?

Answer 8

1) Extra Pyramidal System (Basal Ganglia)
2) Cerebellar System
3) Sensory input - joint position

Question 9

What are the common symptoms of Parkinson’s?

Answer 9

TRAP

Tremor, Rigidity, Akinesia, Postural instability

Question 10

What are the symptoms of Cerebellar dysfunction?

Answer 10

Dysdiadokinesia
Ataxia
Nystagmus
Intention Tremor
Slurred Speech
Hypotonia