Week 4 - Bone Tissue

• Diaphysis (shaft of long bone) • Epiphyses • Metaphyses

Responsible for supporting the weight of the body as columns and, at the same time, increase the power of the muscles working as a lever.

Aids in the growth of bone length

• Growth in length occurs at the growth plate (epiphyseal plate) • Transfer loads from weight-bearing joint surfaces to the diaphysis (In adults)

The growth plate (Epiphyseal plate) is located in the metaphyses (which is located between the middle and the end of the long bones)

Connective tissue sheath that wraps around the external surface of bone wherever it isn’t covered by articular cartilage

• Protects bone • Point of attachment for ligaments and tendons • Nourishes bone tissue • Helps in fracture repair

The Periosteum is rich in sensory nerves which are very sensitive to tearing or tension

• Compact - Spongy

Dense, smooth solid on the outer layer of bones

• Protection and support of spongy bone, blood vessels and nerves • Resists stresses produced by weight and movement

• Made up from Osteons that are arranged parallel to the diaphysis of long bones (this gives the long bones strength) • Within and between the osteons is extracellular fluid that contains osteocytes to maintain the bone tissue (this enables the exchange of nutrients and oxygen and removal of waste) • Osteons give the strength and resistance to compact bone

Always in the interior of bones

• Lightweight which means it can be moved by skeletal muscle contraction • Protects bone marrow (red and yellow)

Nutrients to osteocytes

• Less dense than compact bone as it contains bone marrow • Fine trabeculae ‘Little Beams’ • Oxygen and nutrients pass from blood vessels that surround the trabeculae • Trabeculae are positioned along lines of stress - resist stress

• SPONGY: • Consists of trabeculae (does not contain osteons) • Forms the interior of the epiphysis of long bones and most of the structures of short, flat bones • Makes bones lighter and easier to move • Houses bone marrow • COMPACT: • Consists of osteons with little space between them • Forms the exterior surface of bones and covers spongy bone • Is the strongest form of bone (protects, supports, resists stress)

• Hyaline cartilage - Fibrocartilage

• Supports external nose (nasal cartilage) • Covers ends of most bones at movable joints (articular cartilage) • Connect ribs to sternum (costal cartilage) • Also in the larynx, trachea, bronchi & bronchial tubes

• Provides smooth surfaces for joint movement - Provides support & flexibility for joints

• At sites subject to both pressure and stretch - Intervertebral discs - Pubic symphysis - Cartilage pads in knee (Minisci)

To support and join structures together

Bone cells

• Water • Collagen Fibres • Crystallized mineral salts