Joints (human Skeleton)

Question 1

What are joints

Answer 1

Places in the body where two or more bones articulate (move) with each other

Question 2

Different types of joints

Answer 2

Fibrous
Cartilaginous
Synovial - ball and socket
Hinge
Pivot
Plane/ gliding

Question 3

What can joints be classified according to

Answer 3

To the material bonding them or to their mobility

Question 4

What are fibrous joints

Answer 4

Held together by fibers, immovable

Eg. Sutures of the cranium

Question 5

Cartilaginous joints

Answer 5

Held together by cartilage, partly move able

Eg. Pubic symphysis and joints btw vertebrae

Question 6

Synovial joints and their classification

Answer 6

Held together by a double layered articulate capsule ,
Have a fluid filled cavity surrounding bones
Freely moveable

Classifies according to the kind of movement that takes place in joint

• ball and socket
• hinge
• pivot
• plane/ gliding

Question 7

This joint is v flexible, allows movement in most directions

E.g a hip joint

Answer 7

Ball and socket

Question 8

Allows bones to move in one plane of direction

Answer 8

Hinge

Eg knee joint

Question 9

Allows a bone to rotate

Answer 9

Pivot

Eg atlas and axis vertebrae

Question 10

Flat bone glides/ slips over another bone

Answer 10

Plane/ gliding joint

Eg carpal bones in wrist

Question 11

Synovial cavity

Answer 11

Contains synovial fluid
Acts as lubricant reducing friction
Helps absorb shock if joint is compressed
Nourishes cartilage

Question 12

Articular cartilage

Answer 12

Creates a smooth surface on articulating bones
Prevents friction
Keeps bone ends from being crushed

Question 13

Articular capsule

Answer 13

Encloses the joint and prevents dislocation

Question 14

Synovial membrane

Answer 14

Secretes synovial fluid

Question 15

Examples of joint injuries and diseases

Answer 15

Bunion
Sprain
Dislocation
Arthritis

Question 16

Bunion

Answer 16

Swelling at base of big toe with calluses and bone spurs
Tight fitting shoes/ inherited
(Enlarged bursa at base of big toe)
BURSAE= flattened sacs lined with synovial membrane found btw ligaments/ muscles/ tendons - prevents them rubbing against bone causing friction

Question 17

Sprain

Answer 17

Stretched torn ligament
Joint is built to withstand tough treatment. Injury caused when it’s forced beyond limits of movement
Kept still till ligament repairs itself
Ligaments have poor blood supply which means healing is slow
Ankle/knee/ lumbar regions most often sprained

Question 18

Dislocation

Answer 18

Injury/ disability caused when the normal position of bone is displaced
Ligaments around joint can often be torn during dislocation
Major trauma
Can cut off blood supply
Must be out back into place otherwise can loose limb

Question 19

Arthritis

Answer 19

Includes many different diseases
Results in stiff, swollen, painful and even deformed joints
Osteoarthritis
Gout
Rheumatoid arthritis

Question 20

OSTEOARTHRITIS

Answer 20

Cartilage in joints breaks down due to wear and tear

Joints become inflexible

Question 21

Rheumatoid arthritis

Answer 21

Chronic inflammatory condition
Joints become swollen , painful, finally deformed
Auto immune disease where body attacks own tissue

Question 22

Gout

Answer 22

Build up of Uris acid crystals in joints
Big toe/ thumb (can occur in any other joint)
Results in swollen , v painful joints. Can become discolor red

Question 23

How do muscles function

Answer 23

Each skeletal muscle has a nerve attached, when nerve impulse sent to muscle - muscle contracts
In skeletal muscle, nerve mostly under voluntary control
When muscle stimulate by a nerve impulse, contract by becoming shorter
Then move back to original position when relaxed
The muscle fibers are pulled back into position by the other muscles that work antagonistic ally
Two types of protein, actin and myosin, filaments slide btw each other making muscle shorter
When nerve impulse comes to muscle along nerve

Question 24

Antagonistic muscles

Answer 24

Skeletal muscle only exert a force by contracting and relaxing
To reverse a muscular movem in opposite directions requires an antagonistic muscle to pull in that direction by contracting
The antagonistic pair of muscles include the flexor (BENDINGM) and the extensor (EXTENDING)

Question 25

Functions of muscles

Answer 25

Move the external and internal body parts
Maintain posture of body
Generate heat
Stabilize joints

Question 26

How is movement brought about

Answer 26

By bones, joints, skeletal muscles functioning together

Question 27

Dystrophin

Answer 27

Stabilizes muscle cell membrane

Question 28

Types of protein in muscles

Answer 28

Actin and myosin

Question 29

What type of control is nerve impulse mostly under

Answer 29

Voluntary

Question 30

Muscular dystrophy

Answer 30

A group of diseases which cause progressive weakness and loss of muscle mass
Abnormal genes( mutation) interfere with the production of proteins needed to form healthy muscles

Question 31

Symptoms and treatment of muscular dystrophy

Answer 31

Begins in childhood

No treatment