Skeletal system

Question 1

function of the skeletal system

Answer 1

1. Provides framework for the body and gives it shape
2. Irregularities on bone surfaces provide attachment points for muscles. When a muscle contracts, the bone it inserts into moves, acting as a lever to help create movement.
3. Protects vital organs e.g. Skull protects the brain
4. Responsible for storing essential minerals such as calcium and phosphorous which contribute to the health and maintenance of bone tissue.
5. Produces red blood cells (RBC’s) in the bone marrow, particularly during high growth years such as childhood and adolescence.

Question 2

Axil and appendicular skeleton

Answer 2

AXIAL SKELETON
Forms the basic central structure to support the remainder of the skeleton

APPENDICULAR SKELETON
Major role is to assist with movement and includes the major limbs. EG: Arms, Legs, Shoulder and pelvic girdles

Question 3

Fibrous joints

Answer 3

No movement at all
Primary function is protection
E.g. bones of the skull, sternum

Question 4

Cartilaginous (slightly movable)

Answer 4

These joints occur where the connection between the bones is made up of cartilage.
Small amount movement possible.
E.g. Between the vertebrae of the spine

Question 5

Synovial

Answer 5

Most common joints in the body, designed to allow movement in at least 1 direction
Cavities between bones are filled with synovial fluid which helps lubricate and protect the bones.
E.g. knee, elbow, wrist, ankle

Question 6

Gliding joints

Answer 6

Bone surfaces are flat and only a small amount of movement is possible in a linear direction – movement occurs when the surfaces slide across each other
These are the most common type of synovial joint in the body
E.g. carpal bones of the wrist, tarsal bones of the ankle

Question 7

Types of synovial joints

Answer 7

1. gliding joints
2. hinge joint
3. pivot joint
4. sadel joint
5. Condyloid joint
6. ball and socket

Question 8

Hinge joint

Answer 8

Only allows movement through 1 plane
Flexion – extension
As the name suggests, the movement of a hinge joint is similar to the action of a door opening and closing
E.g. Knee, elbow, fingers, toes

Question 9

Pivot joint

Answer 9

This type of joint allows one bone, with a ring shaped structure, to pivot around another, creating turning motions without sideways displacement or bending

Question 10

Saddle joint

Answer 10

Characterised by two bones that fit together the same way as a rider on a saddle.
This sort of articulation creates bending motions in several directions and allows the thumb to be placed across the palm of the hand
E.g. carpal and metacarpal bones of the thumb

Question 11

Condyloid joint

Answer 11

Otherwise known as ellipsoidal or ovoid joint, the oval shaped surface of 1 bone fits into the depression of another
This allows flexion/extension, abduction/adduction and circumduction. E.g. Joint between the carpals of the wrist and the radius

Question 12

Ball and socket joint

Answer 12

The ‘ball’ of one bone fits into the cup or ‘socket’ of another
Allows for stable movement in several directions including the following; Flexion – extension,
Adduction – abduction, Rotation, E.g. Hip joint, shoulder joint