Skeletal and Muscular System

How many bones in ADULT body?

206 bones (207 including yk what 😏)

What are bones made of?

Living tissue that repair themselves, collagen, and minerals like calcium and phosphorus.

Texture of inside and outside of bone?

The outer texture is smooth and dense, while the inner texture is spongy and porous, providing strength and reducing weight filled with bone marrow.

Joint

Where two bones meet.

Ligament

A connective tissue connecting bone-to-bone.

Tendon

A connective tissue connecting bone-to-muscle.

How are bones protected at the joint?

By tissue and cartilage that cushions and stabilises them.

Three types of muscle

• Skeletal muscle → attached to bone for movement (voluntary)

• Cardiac muscle → coordinating heartbeat (involuntary)

• Smooth muscle → lines organs and blood vessels (involuntary)

Different joints

• Hinge joints → one direction (e.g elbow and knee)

• Ball-and-socket joints → allow multi-directional movement (e.g. shoulder and hip)

• Pivot joints → allow rotational movement (e.g. neck)

Bones in ear: (ossicles)

• Malleus (hammer)

• Incus (anvil)

• Stapes (stirrup) → smallest bone