Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Control of human movement > Block 2 - Sensory and motor neurons > Flashcards

Block 2 - Sensory and motor neurons Flashcards

1
Q

What are the 2 types of resistance in neurons?

A

Longitudinal
Medial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the ‘perfect’ neuron comprised of in terms of resistance?

A

High medial resistance
Low longitudinal resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is decay defined by?

A

Space constant and time constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is space constant? Give an equation

A

How far the voltage travels
Square root of medial / longitudinal resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is time constant? Give an equation

A

How fast a voltage travels
Medial resistance x medial capcitance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is capacitance?

A

Tendency of the membrane to store charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do you increase conduction velocity?

A

Increase space constant
Decrease time constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the resting potential of mammalians?

A

-60-70 mA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the actions of hyperpolarisation and depolarisation

A

H - increases potential, so less likely to fire
D - decreases potential, so more likely to fire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does the sodium-potassium pump work?

A

For 1 molecule of ATP:
2 x potassium in
3 x sodium out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When does voltage gated ion channels open?

A

When depolarisation reaches threshold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 3 states of a sodium channel?

A

Open
Closed
Deactivated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the states of a potassium channel?

A

Open
Closed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the process of an action potential.

A

Cell membrane depolarises
Threshold reached = sodium channels open
Further depolarisation
Adjacent channels open
Potassium channels open slowly
Sodium channels close and temporarily deactivated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

By which feedback is sodium and potassium controlled?

A

Sodium - negative feedback
Potassium - positive feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the refractory period ensure?

A

AP travel in one direction - orthodromic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which electrode depolarises neurons?

A

Cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name 2 rate limiting factors of an AP?

A

Na+/P+ channels opening and closing
Temperature

19
Q

What is the effect of diameter on neuronal conduction?

A

Space constant increases
Time constant stays the same

20
Q

Where does passive ionic conduction occur in neurons surrounded by myelination?

A

Nodes of Ranvier

21
Q

Does myelination increase medial or longitudinal resistance?

A

Medial

22
Q

What are the slowest types of fibres?

A

C-fibres - pain fibres

23
Q

In which direction does artificial stimulation of a neurone occur?

A

Both directions

24
Q

Conduction velocity equation

A
25
Q

Which conditions are a result of demyelination?

A

Multiple-sclerosis
Guillan-Barre syndrome

26
Q

Process of AP at a neuromuscular junction.

A

AP stimulates release of neurotransmitter across NMJ
AP spreads across sarcolemma and down T-tubules
Stimulates release of calcium
Calcium binds to troponin and allows formation of cross bridge cycle

27
Q

Where is the cell body of the motor neuron found?

A

Ventral horn

28
Q

What is a motor unit?

A

A motor neurone and all the fibres it innervates

29
Q

What 3 factors affects fusion of twitches to produce tetanic force?

A

Fatigue
Temperature
Fibre type

30
Q

What are the 2 mechanisms that allows generation of extra force?

A

Recruiting more motor units
Increasing frequency of firing

31
Q

What does high innervation of muscle mean?

A

Lower of precise control

32
Q

What are fast fibres characterised by in terms of an AP?

A

Higher resting membrane potential
Great sodium channels
Faster AP

33
Q

Which type of contraction produce more force, but EMG is smaller?

A

Eccentric

34
Q

When is force optimal?

A

When cross-bridge overlap is optimal

35
Q

Why is force well maintained at 50% force?

A

Greater reserve capacity and recruits additional fibres

36
Q

Why does force reduce at 100%?

A

No reserve capacity
Muscle wisdom

37
Q

What is muscle wisdom?

A

Build-up of metabolites
Suppressing motor neuron firing
Decreasing force

38
Q

Why does muscle wisdom occur?

A

Reduce neuronal fatigue
Maintain control of fine skills

39
Q

What is high frequency fatigue and when does it occur?

A

Caused by high continuous frequency stimulation
Recovers immediately
Due to failure of AP spreading across sarcolemma and t-tubules

40
Q

What is low frequency fatigue?

A

Caused by intense exercise
Days of recovery
Due to damage to the tissue which impairs calcium release from SR

41
Q

What is twitch interpolation?

A

Increase force = decrease twitch interpolation
Increase fatigue = increase twitch interpolation

42
Q

Methods of measuring muscle activity?

A

EMG
AMG
Ultrasound

43
Q

How do you measure changes in control due to fatigue?

A

EMG/AMG

Control of human movement (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions