Mrs. Neistadt

Biology

Ch 15: Support and Movement

Ch 32.2: The Skeletal System

The Skeletal System

1. *Support: the skeleton holds your body up and gives you shape.

2. *Protection: The skull protects the brain, vertebrae protect the spinal column, rib cage protects the heart, lungs, and other organs.

*Five Functions of the Skeletal System:

3. *Movement: Bones are attached to muscles to help your body move.4. *Formation of blood cells: Red bone marrow produces red blood cells, white blood cells and platelets.5. *Storage: bones store minerals such as calcium and phosphorus

*Five Functions of the Skeletal System:

* There are 206 Bones in an adult skeleton.

These are divided into two types:The Axial Skeleton

includes the skull, vertebral column, the ribs, and the sternum.

The Appendicular: the shoulders, arms, hands, hips, legs, feet

(pg 941)

The Skeletal System

Classification of Bones on the Basis of Shape

*Cartilage- tissue that is tough but flexibleExamples: End of the nose; Ears

What are Bones Made of?

*The membrane covering the bone is the periosteum.This membrane brings nutrients to the bone.

*The outer layer of all bones is composed of Compact Bone.

*Compact Bone is dense and strong; it provides strength and protection.A network of tubes runsThrough the compact boneThese tubes contain bloodVessels and nerves.

What Are Bones Made of?

*Spongy bone is found in the center of short or flat bones, and at the end of long bones.

*Spongy bone varies from bone to bone.

What Are Bones Made of?

*There are two types of Bone Marrow:

*Red Bone Marrow- is active. It produces red blood cells, white blood cells and platelets. Children’s bones have more red bone

marrow than adults’.Red bone marrow is found in the

humerus bone of the arm, femur, sternum, ribs, vertebrae and pelvis

*Yellow Bone Marrow- is inactive. It consists of stored fat. Is found in many other bones.

What Are Bones Made of?

*A Fracture is a broken or cracked bone.*A simple fracture is when a bone breaks, but

does not come out through the skin.*A compound fracture is when a bone breaks

and the bone protrudes through the skin.*A stress fracture is a thin crack in the bone.

When Something Goes Wrong…

Upon injury, endorphins blood the brain to reduce the amount of paint felt. (this is temporary)

The injured area begins to swell.A blood clot forms between the broken ends of the

bone.New bone cells begin to form as a mass of cartilage.After a few weeks, the callus made of spongy bone

begins to surround the fracture.Then the spongy bone begins to be replaced by

compact bone.*Calcium, age, nutrition, location and severity are all

factors in how long a bone repair will take.

How Bones Heal Themselves…

On a separate paper: Complete the handout on bones…

Practice wksht #144

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