Reflexes

Question 1

What is the stretch reflex?

Answer 1

It is the reflex contraction in response to ch in the muscle detected by the muscle spindle as a negative feedback mechanism.

Question 2

What is proprioception?

Answer 2

a continuous loop of feedback between sensory receptors throughout your body and your nervous system.

Question 3

Define the motor unit

Answer 3

The muscle fibers innervated by a single motor neuron.

Question 4

Define a motor neuron pool.

Answer 4

The number of motor neurons innervating a single muscle

Question 5

What are the two types of alpha motor neurons and what do they innervate?

Answer 5

Alpha: extrafusal
Gamma: intrafusal

Question 6

State the features of type I slow twitch muscle fibers.

Answer 6

Aeorobic
Large amounts of mitochondria 
Contractile proteins: Troponin I slow  Alpha actinin 2
High myoglobin content 
Red
Endurance muscle
High citric acid cycle rate

Question 7

State the features of type II fast twitch muscle fibers.

Answer 7

Used for quick powerful movements
High glycogen content
Few myoglobin and mitochondria
A lot of glycogen and glycolysis enzymes
Contractile proteins: Troponin I fast and alpha actinin 2 and 3
Low citric acid cycle rate

Question 8

Define the “resting length”

Answer 8

The length of the muscle at which the active tension is maximal