1. Purpose of the Skeletal system
Shape and Support: framework
Protection: heart and lungs surrounded by ribs,
spinal cord surrounded by vertebrae
and brain surrounded by skull.
Storage: keep minerals and fats
Movement: muscles pull bone to move the body
Blood Cell Formation: Inside bones

2. Bones a living organ made of several different tissues
bones start out as cartilage, a smooth, slippery, thick, flexible layer that does not contain blood vessels or minerals; acts as a shock absorber and helps to reduce friction when bones rub together
a living organ made of several different tissues
Inside a Bone
Compact Bone: no visible open spaces, solid, makes up most of
a bone’s mass
Spongy Bone: has many open spaces filled with red marrow,
provides strength and support
Marrow: soft tissue
Red marrow: makes red blood cells
Yellow marrow: stores fat

3. Joints Joint: place where two or more bones connect
kept together by strong elastic bands called ligaments
Types
sliding joint: allow bones to glide
over one another
ball-and-socket joint: allows free movement in all directions
hinge joint: allows you to flex and extend.

4. Diseases and Complications
Arthritis : pain and swelling around the joints due to cartilage being worn away
Osteoporosis : bones become overly porous, weak, and brittle.
Fracture : A break in the continuity of bone
Sprains: an injury to a joint caused by the ligament being stretched too
far