The functions of the skeleton (as part of a healthy, active body)

• Shape and support
(allowing good posture)

• Movement
Muscles attach to bones and create movement (levers) around joints

• Protect internal organs

• Produce red and white blood cells

• Store minerals

• Label the bones on the skeleton

• Fibrous or fixed no movement
• Cartilaginous
• Synovial
slight movement
freely moveable

• Movement in one plane only
• Eg knee, elbow

• Only allows rotation
Eg neck vertebrae when turning head

• Biaxial movement i.e. in 2 planes
Eg playing a badminton shot

• When two flat surfaces glide over one another
Eg carpal bones in wrist when playing hockey

• When concave surface meets convex as in thumb gripping tennis racket

• When a round head of bone sits in a socket – allows wide range of movement
Eg hip, shoulder

• Soft connective tissue
• Babies skeleton is mainly cartilage – through process of
‘ossification’ mostly becomes bone
• Has no blood supply
• Connective tissue between bones
• Tough, resilient, keep joints together & stable
• Prevent extreme movement
• Resist dislocation

• Yellow elastic
• Hyaline (blue) articular
- flexible (ear lobe)
- on articulating surfaces of bones.
Protective - allows movement by limiting friction. Thickens through exercise
• White fibro - tough shock absorber, eg semi-lunar cartilage in knee joint

• Repeated small injuries can lead to cartilage tears
• Degeneration (wear and tear of meniscus cartilage)
• Cartilage is slow to heal as it doesn’t have a blood supply
• Ligaments can sprain or tear
• Medial/cruciate – common knee ligament injuries

• 1. explain how the skeletal system responds to exercise (5)
• 2. name the two most common forms of arthritis and describe their causes (6)
• 3. which category of person is most likely to suffer from osteoporosis and what factors could contribute to this (3)

• short term – in joints stimulates secretion of synovial fluid, which becomes less viscous = greater range of movement
• longer term – connective tissue becomes more flexible. With time improved range of movement becomes more sustained. Bone increases in density = stronger = less risk of osteoporosis.
Hyaline cartilage, tendons and ligaments thicken
= reduced risk of injury. Bone mineral content higher

• Osteoarthritis – caused by ageing and general wear and tear, injury, overweight
• Rheumatoid – immune system attacks cells within joint capsule. Women more at risk, also genetic predisposition, smoking and obesity

• Women over 60
• Inadequate calcium and vitamin D intake
• Lack of weight bearing exercise