PE paper 2

Structure of the synovial joint and movements

Hinges.

Like a hinge on a door

Bones more in one direction back and forth

E.G. knees finger tows elbows and ankles

Ball and sockets

Ball shape surface of one rounded bone fits into the cup

Let’s the joint move in any direction

Most mobile in the body

E.G. hip joint shoulder joint

Flat bones- protection

Short Bones-fine moter movements

Long bones

Features- cylinder like shape longer than it is wide

Function- .movement and support

Example- d femur tubular tibia metarcarples humerus metacarpals phalanges

Short bones

Features- cube like shape not equal in length or with or thickness

Function- provide stability support while allowing some motion

Example- carpals and tartlets

Flat bones

Features- thin and curved

Function- points of attachment from muscles, protectors of vital internal organs

Examples- sternum ribs scapula and cranium

Joint-where 2 or more bones meet E.G. knees finger tows shoulder and elbow hips

3 different types of joints:

Immovable (fixed)- cranium

Slightly movable- vertebrate column

Freely moveable- also known as synovial joints allow greatest movement e.g. knees shoulders and hips

Structure of a joint

Functions:

Synovial membrane- lines the capsule and produces synovial fluid

Synovial fluid- lubricates the joint allowing the part to move freely

Joint capsule- tough fibre that surrounds the joint holds the fluid in place

Bursae- fluid sack which help reduce friction in the joint

Cartilage- covers the ends of bones providing a smooth friction free surface also helps absorbs shock

Ligaments- join bone to bone help stabilise joints

Tendon- joins muscle to bone