MS System: Joints and Muscles

Question 1

Function of joints?

Answer 1

facilitate growth and transmit forces

Question 2

Classification of joints by movement?

Answer 2

• synarthroses - barley move
• amphiarthroses - move a little
• diarthroses - very movable

Question 3

Classification of joints by soft tissue structure?

Answer 3

• fibrous
• cartilaginous
• synovial

Question 4

Fibrous joints?

Answer 4

joined by dense fibrous network

• sutures - between skull and vault bones
• syndesmosis - fibrous membranes between bones - radioulnur (ankle area)
• gomphosis - peg and socket - teeth in jaw

Question 5

Cartilagenous joints?

Answer 5

> primary cartilaginous joints - synchondrosis
bone-hyaline cartilage-bone
secondary cartilaginous joint - symphysis
bone-hyaline cartilage-fibrocartilage-hyaline cartilage-bone

Question 6

Primary cartilaginous joints?

Answer 6

synchondrosis
bone-hyaline cartilage-bone
- very strong, no movement
- first rib and sternum, epiphyseal plates in growing bones

Question 7

Secondary cartilaginous joints?

Answer 7

symphyses
bone-hyaline cartilage-fibrocartilage-hyaline cartilage-bone
- joints of sternum, intervertebral disks, pubic symphysis
- joints of midline
- limited movement

Question 8

Synovial joints?

Answer 8

• very movable

- friction free

Question 9

Features of synovial joints list? (8)

Answer 9

• fibrous capsule
• articular cartilage
• synovial membrane
• synovial fluid
• intra-articular disk
• bursae
• synovial sheaths
• articular cavity

Question 10

Fibrous capsule?

Answer 10

• collagen fibres

- may be thickened along lines of stress to form ligaments (restrict movement) intrinsic and extrinsic ligaments

Question 11

Articular cartilage?

Answer 11

• hyaline cartilage
• creates frictionless surface
• poor blood supply - slow healing

Question 12

Synovial membrane?

Answer 12

• collagenous tissue that lines fibrous capsule

- secretes synovial fluid

Question 13

Synovial fluid?

Answer 13

• hyaluronic acid, lubricant, few phagocytic cells
• reduces friction between articular surfaces
• alignment go glycoprotein molecules changes with excersice - decreases viscosity so that lubrication improves - thixotropic
• provides nutrients and o2 for articular cartilage
• removes waste

Question 14

Intra-articular disk? (meniscus)

Answer 14

• fibre-cartilage

- found in joints with rotatory movements

Question 15

Bursae?

Answer 15

• prevent rubbing
• closed sacs lined with synovial membrane - lubricated with fluid
• found where friction occurs - between skin and bone, tendons and bone

Question 16

Synovial sheaths?

Answer 16

• specialised bursae that surround tendons where they are subject to pressure
• found in hand and foot

Question 17

What determines the range of movement of a joint?

Answer 17

shape of articular surface

• ball and socket joint - three planes
• hinge joint - one plane

Question 18

What factors influence joint stability?

Answer 18

• shape of bones
• strength and positions of the ligaments - stretching
• tone of the surrounding muscles - continuous contraction of muscle

Question 19

What is osteoarthritis?

Answer 19

degenerative disease

• articular cartilage
• weight bearing joints

Question 20

What is rheumatoid arthritis?

Answer 20

autoimmune disease

- changes in synovial lead to destruction of articular cartilage

Question 21

What are the three types of muscle?

Answer 21

• skeletal - voluntary, striated
• visceral - involuntary, smooth
• cardiac - involuntary, striated

Question 22

Function of deep fascia?

Answer 22

divides limbs into compartments

Question 23

What are the muscle components of a functional group?

Answer 23

compartments contain groups of muscles that share a function

• prime mover - main participant in movement
• synergists - other muscles
• antagonists - oppose movements for stability

Question 24

How are muscle fibres arranged?

Answer 24

in bundles or fasciculi

Question 25

The connective tissues that cover muscles?

Answer 25

support nerves and capilaerire
> endomysium - separates muscle fibres
> perimysium - lies between fasculi
> epimysium - dense sheath on surface

Question 26

Skeletal muscle differentialtion?

Answer 26

myosatelite cells differentiate into myoblasts which mature into myocytes

Question 27

What inhibits the process of skeletal muscle differentiation?

Answer 27

myostatin

Question 28

How do muscles cause movement?

Answer 28

when stimulated by nerves muscles contract causing tension that causes movement

Question 29

How do muscles attach to bone?

Answer 29

• directly to periosteum via fleshy muscle fibres
  or
• indirectly to periosteum via tendons