pe muscles

Fibrous joints

No movement. Bones are held tightly together.

Cartilaginous joints

Slight movement. Bones are joined by cartilage.

Synovial joints

Free movement. Most common joint. Filled with synovial fluid.

Cartilage

Protects bones by reducing friction and acting as a shock absorber.

Ligaments

Connect bone to bone and stabilise joints.

Tendons

Connect muscle to bone and help create movement when muscles contract.

Ball and socket joint

Example: shoulder, hip.

Hinge joint

Example: knee, elbow.

Pivot joint

Example: neck (atlas/axis), forearm (radius/ulna rotation).

Saddle joint

Example: thumb joint.

Gliding/Plane joint

Example: wrist bones, ankle bones.

Condyloid (ellipsoid) joint

Example: wrist joint (radius + carpals).

Flexion

Bending a joint; angle between bones decreases.

Extension

Straightening a joint; angle between bones increases.

Abduction

Movement away from the midline of the body.

Adduction

Movement towards the body's midline.

Circumduction

Circular movement combining flexion, extension, abduction, adduction.

Rotation

A bone turning on its axis.

Isometric contraction

Muscle contracts but does NOT change length → no movement.

Isotonic contraction

Muscle changes length and movement occurs.

Slow twitch fibres

Used for endurance and work for a long time.

Fast twitch fibres

Used for power and speed; tire quickly.

Skeletal system

Supports the body, protects organs, allows movement, produces blood cells, stores minerals (like calcium).

Muscular system

Moves the body, maintains posture, produces heat.

Skeletal muscle

Voluntary muscle; examples include biceps and quadriceps.

Smooth muscle

Involuntary muscle; examples include stomach and intestines.

Cardiac muscle

Only example is the heart (but the heart has different chambers).