BTEC Level 3 Unit 1: Skeletal System

Chapter A: Skeletal System 

A1. Bones in the body:

Skull: Cranium, Mandible (Jaw) 

Spinal Column: (7) Cervical, (12) Thoracic, (5) Lumbar, (5) Sacrum, (4) Coccyx

Clavicle (collar bone) 

Sternum (breast bone)

Scapula (back of shoulder)

(24) Ribs 

Arm: Humerus, Ulna (under), Radius

Hand: Carpals, Metacarpals and Phalanges

Pelvis: Made up of three bones ilium, pubis and ischium

Leg: Femur, Patella, Tibia (top) and Fibula

Feet: Tarsals, Metatarsals and Phalanges

A1.2 Types of Bone

Long Bone: Longer than they are wide. Dense to provide strength. Act as lever. Produce white blood cells (WBC) and platelets.

Short Bone: Wider than they are long. Act as shock absorbers as well as providing support and stability.

Irregular Bone: Offers protection, some offer muscle attachment and provide movement.

Flat Bone: Provides protection and muscle attachment

Sesamoid Bone: Reduce friction across a joint

A1.3 Areas of the Skeleton

Axial Skeleton: Central area of the skeleton includes: the spine, skull and rib cage

Appendicular Skeleton: Bones not within the core area of the skeleton including the upper and lower limbs and the pelvis.

Postural Deviations:

Natural Alignment: Natural curvature of the spine refers to having good posture due to the correct position of the three natural curves.

Scoliosis: (S-Shape) An abnormal curvature of the spine within the thoracic region which curves laterally. Often found in children at an early age as it is inheritable.

Kyphosis: (hunchback) Excessive outward curve of the thoracic region of the spine resulting in a hunchback appearance. Caused by having poor posture or deformity of the vertebrae.

A1.4 Process of Bone Growth:

Ossification: The process of rebuilding or forming of bone

Osteoclasts: Remove/reabsorb broken or splintered bone

Osteoblasts: Cells that bring calcium to the bone to build up layers of bone which makes them stronger.

(If you find this hard to remember then think how the osteoblasts blast on the calcium to rebuild the bone)

Growth of bones occurs at the Epiphyseal Plates. As you get older the epiphyseal plates become an Epiphyseal Line as the plates fuse together as they are no longer needed.

A2.1 Functions of the Skeleton:

Supporting Framework- Keep you upright

Protection- Prevents damage to organs

Attachment of Skeletal Muscle- Allows movement

Blood Cell Production: WBC and…