1. Structure and Movement
Chapter 17
Structure and Movement

2. Section 1- The Skeletal System
All the bones in your body make up your skeletal system.
5 Major Functions.
1. Gives shape and support to your body.
2. Protects your internal organs. Ex. Skull encloses the brain.
3. Major muscle are attached to bone and help them move.
4. Blood cell formation
5. Stores minerals

3. Bone Structure Periosteum Compact bone Spongy bone Cartilage
Tight-fitting membrane that makes up outer covering of bone.
Under the periosteum are compact and spongy bone.
Compact bone
Directly underneath periosteum
Gives bones strength
Spongy bone
Found on the ends of bone
Makes bone lightweight
Cartilage
Flexible tissue without blood cells that cushions ends of bones.

4. Bone Formation Osteoblasts- build up bone.
Osteoclasts- breaks down bone tissue.
Marrow
Substance that produces red and white blood cells inside bones.

5. Joints
Joint
Where two or more bones meet.
The bones are held in place at these joints by a tough band of tissue called a ligament.
Immovable Joint
Allows little or no movement
Ex. Skull and Pelvis
Movable Joint
Joint that allows range of movement.
Ex. Ball and socket, pivot, hinge
Ball and socket- attaches your arm and shoulder.

7. Section 2- The Muscular System
Muscle
Organ that contracts and relaxes. Makes all your daily movements possible.
MORE THAN 600 MUSCLES MAKE MOVEMENT POSSIBLE!!!!!
Tendons
Thick bands of tissue that attach muscle to bone.
Voluntary Muscles
Muscles that you are able to control
Ex. Arm, Hand, and Leg
Involuntary Muscles
Muscles you can’t control consciously
Blood moves through blood vessels
Food is moved through your digestive system

8. Classification of Muscle Tissue
Three types of Muscle:
1. Skeletal
2. Smooth
3. Cardiac
Skeletal
Muscles that look striped and are used to move bones. Always work in pairs. When on contracts the other relaxes.
Smooth
Involuntary muscles that have NO striations
Cardiac
Involuntary muscles with straitions in your heart.

9. Section 3- The Skin The LARGEST organ in your body!!!! Epidermis
Outermost layer of your skin. (thinnest)
Cells of the epidermis are constantly rubbing off, being replaced, and dying off.
What pigment gives the
skin color??
Melanin!
Exposure to ultraviolet rays,
increases melanin production.
Dermis
Layer of tissue under the epidermis.
Contains blood vessels, nerves, muscles, oil and sweat glands.

10. Skin Functions Skin Protects Your Body:
1. Prevents internal damage (injury)
2. Prevents excess water loss from body tissues
3. Glands secrete fluids that destroy bacteria
4. Formation of vitamin D.
5. Regulates body temperature
Sweat glands help rid the body of wastes by releasing water and salt.

11. Skin Grafts
pieces of skin that are cut from one part of a person’s body and then moved to the injured or burned area where there is no skin.