The Skeletal System Ch. 14 Sect 1

Functions of the Skeletal System The skeletal system contains bones, and other structures that connect , protect and support other functions in the body. Bones provide support (helping you sit up, stand and raise your arm) Bones help with movement by being attached to muscles. Bones protect organs and tissues Bones produce red blood cells and store fat and calcium.

Structure of Bones 2 main types of bone tissue: 1. Compact Bone Tissue – hard, outer portions of the bone composed of fibers. Ex. Arm 2. Spongy Bone Tissue – found at the end of long bones, contains small holes and is less dense than compact bone. Ex. Wrist Bone Marrow – located inside of bones, made of tissue. 2 types: Red bone marrow(produces red blood cells), Yellow bone marrow (stores fat).

Cont.’ of Bone Structure Cartilage- is a strong, flexible tissue that covers the ends of bones. Prevents bone surfaces from rubbing against each other. Periosteum – membrane that surround the bone. Contains blood vessels, nerves and produces new bone tissue. Bone formation starts with cartilage and is replaced by bones. Growth plates are regions on bones that produce new bone cells.

Joints Is where two or more bones meet. Provides flexibility and allows movement. Ligament – tissues that connect bone to bone Ligaments connect bones at joints but do not protect the bones. 2 types of joints: Immovable and Movable

Bone Injuries and Diseases Fracture (break in a bone) Arthritis (irritated or inflamed joints) Osteoporosis (weaken & brittle bones)

Healthy Bones, Skeletal System, & Homeostasis Exercise keeps bones healthy. Balanced diet keeps bones healthy. Homeostasis – ability to maintain a stable internal environment. All body systems must work together to maintain homeostasis.