CHAPTER 14

THE SKELETAL SYSTEM

• The skeletal system consists of 206 bones and each one has its own function
• Every bones has two main parts, outer layer and inner layer
• The outer layer is hard compacted bone
• The inside is a spongy bone made of red bone marrow
• Bones are categorized by there shape

THE SKELETAL SYSTEM

• Cartilage: is a strong, flexible connective tissue.
• Ossification: the process wich bone is formed, renewed, and repaired.
• Ligament: a bandof fibours, slightly elastic connective tissue that attaches one bone to another.
• Tendon: a fibrous cord that attches muscle to the bone.

THE SKELETAL SYSTEM

• Joints are points at which bones meet.
• Osteoporosis: a condition in which there is progressive loss of bone tissue.
• Bone tossue loss is a part of aging but by eating foods containing calcium, vitamin D, and phosphorus can hel keep your bines healthy.
• Getting bines scan can help detect signs of osteoporosis.

THE MUSCULAR SYSTEM

• Your muscles are always at work even when you are sleeping even though it may not seem like it.
• Muscles are made up of hundereds of long cells called muscle fiber.
• When muscles are stimulated they shorten and contract.
• When they relax the stretch out.

THE MUSCULAR SYSTEM

• Smooth muscles: muscles that act on the lining of the body's passageway and hollow intermal organs.
• Skeletal muscles: muscles attached to the bone that causes body movements.
• Flexor: muscle that closes a joint.
• Extensor: muscle that opens a joint.
• Cardiac muscle: type of straighted muscle that forms the wall of the heart.

THE MUSCULAR SYSTEM

• There are three types of muscle in the body, smooth, skelatal, and cardiac muscle.
• Physical activities will keep your muscles healthy and strong.
• Tendinitis: the inflammation of a tendon.
• Tendinitis can be a result of injury, overuse, or natural aging.
• Hernia: organ or tissue protrudes thriugh an area of weak muscle.

THE NERVOUS SYSTEM

• Nervous system allows your body parts to communicate with other parts.
• Neurons: nerve cells.
• Cell body regulates the production.
• Dendrites branched structures that extend from the sell body.
• Axons transmit impulses away from the cell bodyand towards other neurons.

THE NERVOUS SYSTEM

• Cerebrum is the largest part of the brain.
• Cerebellum is the second largest part of the brain.
• Brain stem: 3 inch long stalk of nerv cells and fiber that connects the spinal cord to the ret of the brain.
• Epilepsy: disorder of the nervous sytem that causes seizures.
• Cerebral: group of neurological disorders that results of damage to the brain.