skeletal and muscle system

Question 1

Types of synovial joint

What type of synovial joint is found at the wrist and what plane/s of movement does it allow?

Answer 1

• Condyloid joint
• Frontal and sagittal movement

Question 2

Types of synovial joint

What type fo synovial joint is found at the elbow, knee and ankle and what plane/s of movement does it allow?

Answer 2

• Hinge joint
• Sagittal movement

Question 3

Types of synovial joint

What type of synovial joint is found at the shoulder and hip joint and what plane of movement does it allow?

Answer 3

• Ball and socket joint
• Frontal, transverse and sagittal movement

Question 4

Types of movement

Sporting example of plantar flexion

Answer 4

Pirouette in ballet
(pointed toes movement)

Question 5

Types of movement

Sporting example of dorsiflexion

Answer 5

Marathon runner, front ankle while taking a step forward (toes face upwards)

Question 6

Types of movement

Sporting example of horizontal flexion

Answer 6

Execution phase of a discus throw at the shoulder joint

Question 7

Types of movement

Sporting example of horizontal extension

Answer 7

Preparation phase of a discus throw at the shoulder joint

Question 8

Typres of muscle movement

3 types

Answer 8

Concentric, eccentric, isometric
(concentric and eccentric are both isotonic contractions)

Question 9

Typres of muscle movement

Concentric

Answer 9

Muscle shortens (agonist)
Causes movement

Question 10

Typres of muscle movement

Eccentric

Answer 10

Muscle lengthens (antagonist)
Controls movement

Question 11

Typres of muscle movement

Isometric

Answer 11

Muscle remains same length while exerting a force
Stops movement

Question 12

Structure and role of motor units in skeletal muscle contraction

What is a motor unit

Answer 12

A motor neurone plus all the muscle fibres it innervates

Question 13

Structure and role of motor units in skeletal muscle contraction

Motor unit function

Answer 13

To carry impluses from CNS to muscle fibres to initiate muscular contraction

Question 14

Types of motor units

Type 1

What is it, sporting example

Answer 14

• Slow twitch oxidative
• Small and produce a low force of contraction over a long period of time
• E.g. marathon, long distance swimming

Question 15

Types of motor units

Type 2a

What is it, sporting example

Answer 15

• Fast oxidative
• The force and time of contraction is between type 1 and type 2b motor units
• E.g. 200-800m running

Question 16

Types of motor units

Type 2b

What is it, sporting example

Answer 16

• Fast glycolytic
• Large and produce the greatest force over the shortest period of time
• E.g. long jump, 100m sprint

Question 17

How is a motor unit stimulated to cause contraction?

Answer 17

• Nerve impulses from the CNS are sent to the motor neuron cell
• And are carried down the axon to the synaptic cleft
• Impulses pass through the synpase to the neuromuscular junction
• Impulses then sent to the muscle fibres to cause contraction
• …in an all or none fashion

Question 18

Motor unit

What is the all or none law

Answer 18

If the action potential is reached, all muscle fibres within a motor unit contract completely or not at all

Question 19

Motor neuron

Resting potential

Answer 19

The neuron at rest
Lower charge inside neuron than outside

Question 20

Motor neuron

Action potential

Answer 20

Electrical activity carried down the axon

Question 21

Motor neuron

Neurotransmitter

Answer 21

Chemical messanger that transmits across synapse and binds to muscle fibres to initiate muscle contraction

Question 22

Motor neuron

Acetyl choline

Answer 22

Neurotransmitter released at neuromuscular junction that travels across synapse