Musculo-Skeletal System (topic 5)

Question 1

Define Epimysium

Answer 1

Thick connective tissue that wraps the muscle belly, allows for movement and carries nerves and blood cells

Question 2

Define Perimysium

Answer 2

Connective tissue that surrounds bundles of muscle fibres

Question 3

Define Fasciculi

Answer 3

Bundles of muscle fibres

Question 4

Define Endomysium

Answer 4

Surrounds each individual muscle fibre

Question 5

Define Slow twitch muscle fibre

Answer 5

Muscle fibre that uses oxygen to produce energy (high oxidative capacity); endurance based activities

Question 6

Define Fast twitch muscle fibres

Answer 6

Muscle fibres that has high glycolytic capacity (anaerobic); speed and power based activities

Question 7

Define a motor unit

Answer 7

The motor neuron and the group of muscle fibres that it controls

Question 8

Define Innervation

Answer 8

A motor neurone transmits a nerve impulse or action potential to the muscle

Question 9

Define the all or none law

Answer 9

Individual muscle fibres within a motor unit contract either fully or not at all - individual muscle fibres cannot partially contract

Question 10

Define multiple unit summation

Answer 10

The strength of a muscle contraction can be increased by recruiting more motor units

Question 11

Define wave summation

Answer 11

Increases tension within a motor unit; rapid stimulus without relaxation produces tetanus

Question 12

Define tetanus

Answer 12

A smooth and sustained muscle contraction produced when a motor unit is stimulated by a series of impulses in quick succession

Question 13

Define proprioceptors

Answer 13

Sensory receptors in muscles, tendons, joints and inner ear; detect motion or position of body or limb by responding to stimulus

Question 14

What is a joint?

Answer 14

Where two or more bones meet and muscles act together to cause movement

Question 15

What are fibrous/ fixed joints?

Answer 15

• Bones at an immovable joint which cannot move
• they overlap or interlock
• they’re held together by a tough fibre
• e.g the skull

Question 16

What are cartilaginous/ slightly moveable joints?

Answer 16

• bones can only move a little
• they’re held together by ligaments
• they are joined by cartilage
• e.g ribs

Question 17

What are synovial/ freely moveable joints?

Answer 17

• bones move freely
• also known as synovial joints
• largest group of joints found in the body (70 in skeleton)
• e.g hips, shoulders, knees

Question 18

What are ligaments?

Answer 18

Elastic straps which join bone to bone, holding the joint together

Question 19

What is cartilage?

Answer 19

Material which covers the end of each bone to help prevent friction between joints

Question 20

What is a joint capsule?

Answer 20

Outer covering of joint that holds bones together and protects the joint.

Question 21

What is the synovial membrane?

Answer 21

Inner lining of the joint capsule which produces synovial fluid

Question 22

What is synovial fluid?

Answer 22

Fluid which surrounds the joint and acts like ‘oil’, lubricating it to allow easy movement

Question 23

What are tendons?

Answer 23

Non-elastic straps which join muscle to bone

Question 24

Ball and socket joint

Answer 24

• allow joint to rotate
• lot of flexibility
• both parts covered by cartilage
• synovial fluid

Question 25

Hindge joint

Answer 25

- like lever and allows 180 degree movement - covered by cartilage - contains synovial fluid - muscles work in pairs to contract and relax to move joint

Question 26

Fixed/ fused joint

Answer 26

- between two bits of bone and don’t move - e.g plates of bone fused to form solid skull - it cannot grow

Question 27

Pivot joint

Answer 27

- bones rotate by 360 degrees - can limit rotation e.g neck - covered by cartilage - contains synovial fluid

Question 28

Gliding joint

Answer 28

- provides flexibility while limiting to prevent injury - contains synovial fluid - bones are flat/ nearly flat to slide over each other - e.g ankles, wrist

Question 29

Saddle/ seller joint

Answer 29

- one bone turned inwards and one outwards - contains synovial fluid - highly flexible joints - e.g thumb, shoulder

Question 30

Condyloid joint

Answer 30

- allows you to flex and extend the joint - can move it side to side - it’s an ovoid articular surface - e.g wrist

Question 31

Name the types of synovial joint

Answer 31

``` 1- ball and socket joint 2- hinge joint 3-pivot joint 4-gliding joint 5-saddle joint 6-condyloid joint ```

Question 32

What is a bursa/ bursae?

Answer 32

Little pad of fat to protect the joint from any impact