Chapter 6: Structure and Movement

•Section 1 - The Skeletal System•Section 2 - The Muscular System

•Section 3 - The Skin

Section 1 – Skeletal SystemBefore we begin, we are going to play a game: I want you to divide the paper in the middle of

the table in half. On one side, I want you to label it Above the

Neck and the other side Below the Neck. Number both sides 1 – 5. Now list 5 body parts that have only 3 letters. You should have a total of 10 body parts listed on

your paper. You will work with the students at your

table only.

Section 1 – Skeletal System Above the Neck1. Eye2. Ear3. Jaw4. Lip5. Gum

Below the Neck1. Rib2. Toe3. Hip4. Leg5. Arm

Section 1 – Skeletal System

Are your bones alive? Yes! Bones are made of a mixture of hard

stuff that makes them strong and many living cells which help them grow and repair themselves. Like other cells in your body, the bone cells rely on blood to keep them alive. Blood brings them food and oxygen and takes away waste.

• Includes ALL the bones in your body

• The Framework of your body and has Five Major Functions.– Gives shape and support to your

body

– Protection of your Internal Organs

– Major Muscles are attached to bones and help them move

– Blood Cells are formed in the center of many bones in soft tissue called red marrow

– Storage of Calcium and Phosphorous compounds, which also makes bones hard.

Skeletal

System

Bone Structure

– Periosteum – a tough, tight-fitting membrane that covers the surface of a living bone. Its blood vessels supply nutrients and its nerves signal pain

– Compact Bone is a hard, strong layer located directly under the periosteum. This layer contains calcium and phosphorous deposits giving the bone its strength, bone cells, and blood vessels.

– Spongy Bone is located toward the ends of long bones and made up of many small, open spaces that make bones lightweight.

• In the centers of long bones are large opening called cavities. These cavities and spongy bone contain marrow.

– Cartilage is a smooth, slippery, thick layer of tissue that covers the ends of bones. Cartilage does not contain blood vessels or minerals. Cartilage is flexible and important in joints because it acts as a shock absorber.

BoneFormation

– Before birth, your skeleton was made of cartilage. Gradually the cartilage broke down and was replaced with bone. Bone-forming cells called Osteoblasts deposit the minerals calcium and phosphorous in bones, making the bone tissue hard.

– At birth, your skeleton was made up of more than 300 bones. As you develop, some bones fused, or grew together, so that now you have only 206 bones.

Joints Any place where two or more bones come together. The bones are held in place at these joints by a tough band of tissue called a Ligament.

– Immovable Joints allows little or no movement. Examples are joints in your skull and pelvis.

– Movable Joints allows the body to make a wide arrange of motions. • Types of Movable Joints – Pivot,

Ball and Socket, Hinge, and Gliding

Joint

Problems

–Arthritis is the most common joint problem.

• The term arthritis describes more than 100 different diseases that can damage the joints.

• All forms of arthritis begin with the same symptoms: pain, stiffness, and swelling of the joints.

Section 2 – The Muscular System

Section 2 – The Muscular System

Movement of the Human Body

- Muscles An organ that can relax, contract, and provide the force to move your body parts

Energy is used and Work is done

Some muscle are continuously moving

Example: Your Heart Beating

Muscle Control Voluntary Muscles = Controllable– Examples – Hand, Arm, and Leg

Muscles

Involuntary Muscles = Uncontrollable– Examples – Heart Beat and Food

moving through your Digestive system

Classification of Muscle Tissue

*All muscle tissue in your body in NOT the same*

Three Types of Muscles1. Skeletal Muscles

More common Attached to bones by thick

bands of tissue called tendons

Striated in appearance

2. Cardiac Muscles ONLY in the Heart Striated in appearance Contracts about 70 times a

minute

3. Smooth Muscles Located in your intestines,

bladders, and other internal organs

Non-striated in Appearance Involuntary muscles that

slowly contract and relax

Working Muscles

Changes in Muscles

How do muscle allow you to move your body?

• One muscle of a pair contracts• The other relaxes or returns to

its original length• Muscles ALWAYS Pull!!!

NEVER Push!!!

Overtime, muscles can become larger or smaller

• Activity increases muscle mass• Inactivity decreases muscle

mass

How Muscles Move Energy is needed for muscles to contract and relax

Muscle contraction releases energy in the form of mechanical energy (MOVEMENT) and thermal energy (HEAT)

• Heat produced by muscle contractions helps keep your body temperature constant

Section 3 - The Skin

Section 3 – The Skin

Skin = Largest Sensory Organ Sensory - conveying nerve impulses from

the sense organs to the nerve centers Skin senses touch, pain, warmth, and

coldness

Skin StructureMade up of 3

Layers

1. Epidermis Outer, thinnest layer of the skin Dead and Water Repellent Thousands rub off New cells continuously made at the

base and move up Contains melanin – pigment that

protects and gives color

2. Dermis Layer of cells beneath the epidermis Thicker than epidermis Contains many blood vessels,

nerves, muscles, oil & sweat glands, and other structures

3. Fatty Layer Below the dermis Insulates the body

Skin Functions 1. Protection- Against injury and disease-causing organisms

- Prevention of water loss

2. Sensory Response- Detect and relay information to the brain

3. Vitamin D Formation- Helps absorb Calcium

4. Body Temperature Regulation- Blood vessels help release or hold heat

- Perspiration eliminates excess heat by evaporation

5. Waste Elimination through Sweat Glands

Skin Injury and Repair

Bruises- Occur when tiny blood vessels beneath the skin burst and leak into surrounding tissue

Cuts- Scab forms to prevent bacteria from entering your body

- Cells from blood vessels fight infections

- Skin cells beneath scab grow to fill in gap of torn skin

Skin Grafts- Pieces of skin that are cut from another part of a person’s own body and moved to injured area