sensory reception 2

Question 1

different types of proprioreceptors

what do they determine

Answer 1

1-muscle spindles: determine muscle length and rate of contraction
2-golgi tendon organs: determine tension of tendons=tension of muscles
3-joint receptors : determines tension of joints, joint angle and rate of angular movement

Question 2

different types of intrafusal fibres?

what nerves are involved and where are they positioned?

Answer 2

chain: nuclei in a line
bag: nuclei connected
gamma motor neurones found in sarcomere ends which contract so end of nerve contracts but centre doesn’t.

Question 3

how do the gamma fibres work?

what would happen if it stopped firing

Answer 3

1- alpha motor fires so entrafusal fibre contracts and muscle shortens
2-gamma motor fires intrafusal fibre contracts and shortens spindle so that brain is informed of movement of muscle.
If it stopped firing;
1a sensory nerve would stop firing which would decrease spindle sensitivity so that brain would no longer be aware of muscle movement.

Question 4

what do the Golgi tendon organs do?

Answer 4

They innervate the tendon at junction between tendon and muscle. they control the stretch of the tendon.
tendons are inelastic so:
tension of tendon=tension of muscle.

Question 5

what is Kinaestesia?

Answer 5

• Define body position

- Define movement in space

Question 6

What do Proprioreceptors define?

Answer 6

• Kinaestesia
• Golgi tendon organs + Muscle spindles define reflexes in the spinal cord
• control voluntary movement

Question 7

How do muscle spindles and GTO lie in relation to muscle fibres?

Answer 7

• Muscle spindles lie in parallel

- GTO lie in series

Question 8

How to the sensory afferents end?

Answer 8

1a end annuspirally

2a end in flower spray ends

Question 9

What happens when agonist stretches?

Answer 9

Increase in spindle discharge- number of APs