Chapter 22
Section 1 Body Organization
Objectives:
• Describe how tissues, organs, and
organ systems are related.
• List 12 organ systems.
• Identify how organ systems work
together to maintain homeostasis.
• Homeostasis is the maintenance of a
stable internal environment in the body.
•When you jump into a lake, homeostasis
helps your body adapt to the cold water.
• Cells Form Tissues A group of similar
cells working together forms a tissue.
Your body has four main kinds of tissue.
• Tissues Form Organs Two or more tissues
working together to carry out a specialized
function form an organ.
Cells  Tissues  Organs  Organ Systems  Organism
• Organs Form Systems Organs that work
together make up an organ system.
• Organ systems work together to maintain
homeostasis.
• Your body has 12 major organ systems.
12 Major Organ Systems
12 Major Organ Systems
12 Major Organ Systems
Systems of the Body and their Functions
System
Function
Integumentary
System
Your skin, hair, and nails protect
underlying tissue.
Muscular System
Your muscles move your bones.
Skeletal System
Your bones support and protect
body parts.
Cardiovascular
System
Your heart pumps blood through
your blood vessels to the rest
of your body.
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Systems of the Body and their Functions
System
Nervous System
Lymphatic System
Digestive System
Endocrine System
Function
Receives and sends electrical
messages throughout the body.
Returns leaked fluid to blood
vessels. It also helps get rid of
germs.
Breaks down the food you eat into
nutrients that can be absorbed in
your bloodstream.
Made of glands that regulate body
functions by sending out chemical
messages.
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Systems of the Body and their Functions
System
Function
Respiratory System
Your lungs absorb oxygen and
release carbon dioxide.
Urinary System
Removes wastes from the blood
and regulates body fluids.
Reproductive System
The male reproductive system
produces and delivers sperm.
Reproductive System
The female reproductive system
produces eggs and nourishes
and shelters the unborn baby.
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Chapter 22
Objectives:
Section 2 The Skeletal System
• Identify the major organs of the skeletal
system.
• Describe four functions of bones.
• Describe three types of joints.
• List three injuries and two diseases that affect
bones and joints.
Bones
• Bones, cartilage, and the connective tissue that
holds bones together make up your skeletal system.
• Bone Structure Bone tissue without any visible
open spaces is called compact bone. Bone tissue that
has many open spaces is called spongy bone. Bones
contain a soft tissue called marrow. (red & yellow)
• Bone Growth Most bones start out as a flexible
tissue called cartilage. Eventually, most cartilage is
replaced by bone. (What are 2 exceptions?)
Four Functions of the Skeletal System
Three Kinds of Joints
• A place where two or more bones meet is
called a joint.
• Joints are held together by ligaments.
Skeletal System Injuries and Diseases
• Bones may be fractured or broken.
•Joints may be dislocated.
• Sprains are caused when ligaments are
stretched too far or torn.
• Arthritis is a disease that causes the joints to
swell or stiffen.
• Osteoporosis is a disease that causes bones
to become less dense.
Chapter 22
Section 3 The Muscular System
Objectives
• List three kinds of muscle tissue.
• Describe how skeletal muscles move bones.
• Compare aerobic exercise with resistance
exercise.
• Describe two muscular system injuries.
• The muscular system is made up of the
muscles that let you move.
•There are three kinds of muscle in your
body:
•Smooth
•Cardiac
•Skeletal
Smooth Muscle
• Involuntary muscle
found in the digestive
tract and the walls of
the blood vessels is
called smooth muscle.
Cardiac Muscle
•Involuntary muscle
found in your heart
is called cardiac
muscle.
Skeletal Muscle
• Muscle attached to
your skeleton for
movement is called
skeletal muscle.
Skeletal muscle can
be voluntary or
involuntary.
Involuntary vs. Voluntary Muscle
Involuntary-muscle action that is NOT under your
control
Ex. Smooth muscle & cardiac muscle
Voluntary-muscle action that is under your control
Skeletal muscles can be both voluntary and
involuntary. You can blink your eyes anytime you
want to, but your eyes will also blink automatically.
3 Kinds of Muscle
Type
Smooth
Cardiac
Skeletal
Illustration
Voluntary or
Involuntary?
Where is it found?
Movement
• Muscles Attach to Bones Tendons are
strands of tough connective tissue that connect
your skeletal muscles to your bones.
• Muscles Work in Pairs Skeletal muscles
often work in pairs. A muscles that bends part
of your body is called a flexor. A muscle that
straightens part of your body is an extensor.
Use It or Lose It
• Resistance Exercise During resistance
exercise, people work against the resistance,
or weight, of an object to strengthen their
skeletal muscles.
• Aerobic Exercise (using oxygen)
Steady, moderately intense activity is called
aerobic exercise. It strengthens the heart
and increases endurance.
Muscle Injury
• A strain is an injury in which a muscle or
tendon is overstretched or torn.
• People who exercise too much can inflame
their tendons, causing tendonitis.
• Some people try to make their muscles
stronger by taking drugs. These drugs are
called anabolic steroids and can cause longterm health problems.
Chapter 22
Section 4 The Integumentary System
Objectives
• List four functions of skin.
• Describe the two layers of skin.
• Describe the structure and function of hair
and nails.
• Describe two kinds of damage that can affect
skin.
The Integumentary System
• Consists of skin, hair, and nails
Functions of Skin
• skin protects you by keeping water in your
body and foreign particles out of your body
• nerves in your skin let you feel things
• regulates your body temperature
• helps get rid of waste chemicals
Two Main Layers of Skin
Skin is the largest organ of your body.
•Epidermis - outermost layer of skin; most of
these cells are dead and filled with a protein
called keratin
• Dermis - thicker layer of skin that lies
beneath the epidermis; has many fibers made
of a protein called collagen that provide
strength and let skin bend without tearing
Hair and Nails
• A hair forms at the bottom of a tiny sac called
a hair follicle. Hair helps protect skin from
ultraviolet light and helps regulate body
temperature in most mammals.
• A nail grows from living cells in the nail root at
the base of the nail. Nails protect the tips of
your fingers and toes.
Skin Injuries
• Skin is often damaged, but fortunately can repair
itself. However, damage to the genetic material in
skin cells can cause skin cancer.