Motor units

Question 1

What does a motor unit consist of?

Answer 1

One motor neuron and all the muscle fibers it innervates. A muscle may have many motor units of different types

Question 2

How do motor units work when muscles contract?

Answer 2

In a nonsynchronous way. Coopration between motor units may alternate between their contraction

Question 3

Cooperation between motor units increase

Answer 3

the efficiency of the muscle

Question 4

What moves loads? What creates force without movement of the load?

Answer 4

• Isometric contractions

Question 5

What is the effect on isotonic contractions during concentric and eccentric action?

Answer 5

Concentric action is a shortening action

Eccentric action is a lengthening action

Question 6

Series elastic elements

Answer 6

Isometric contractions

Question 7

Sarcomeres shorten while elastic elements stretch, resulting in little change in overall length

Answer 7

Isomteric contractions

Question 8

What is the function of isometric contractions?

Answer 8

Sarcomeres shorten while elastic elements stretch, resulting in little change in overall length

Question 9

What occurs during isotonic contraction?

Answer 9

The muscle contracts, shortens, a creates enough force to move the load

Question 10

What happens during isometric contraction?

Answer 10

The muscle contracts but does not shorten/ The force cannot move the load