Human%20Body%20Systems%20Technology%20Project

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Human Body Systems Technology Project

• by R. Leonard

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Human Body SystemsTHE DR. I.I.L. MCSNEER WAY

• Digestive
• Respiratory
• Integumentary
• Immune
• Lymphatic
• Muscular
• Circulatory
• Skeletal
• Nervous
• Endocrine
• Excretory
• Reproductive

And Levels of Organization
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Human Body Systems

• This slide presentation is meant to help you
  study the major systems of the human body.
• Use it as an introduction or as a review. Follow
  the instructions as you move along to explore and
  learn. You can go through the entire program
  slide by slide, or you skip to focus on any one
  system.

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Believe it or not, you are organized!
http//www.parentingpress.com/pics/sock_cvr.jpg

• The main levels of organization are
• Cells, Tissues, Organs, Organ Systems, and You
  (the Organism).

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Can you identify label the 3 levels of
organization shown here?
Well, at least your body is!
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Levels of Organization The Human Body has
several layers of organization beginning with
the simplest and becoming more complex.
Answers to previous slide cell, tissue, organ
(small intestine).
http//www.bmb.psu.edu/courses/bisci004a/chem/leve
ls.jpg
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By the way, is your room organized like this!?!?
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Here They Are Your Body Systems (Part 1).
http//www.agen.ufl.edu/chyn/age2062/lect/lect_19
/147a.gif
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And Your Body Systems (Part 2)
http//www.agen.ufl.edu/chyn/age2062/lect/lect_19
/lect_19.htm
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So Lets Begin!
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DR. I.I.L. MCSNEER PresentsYour Digestive System
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Your digestive system is like a complicated
chemical processing plant, and performs many
functions.
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What major tasks does your digestive system help
you accomplish?
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Your Digestive System

• breaks down food into molecules the body can
  absorb.
• passes these molecules into the blood to be
  carried throughout the body.
• works to eliminate solid wastes from the body.

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The Parts of Your Digestive System
How well do you know them?
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Label the parts of your digestive system on your
handout then correct them using the following
slide.
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Parts of Your Digestive System
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Now for the Digestive Journey
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The Digestive Journey

• Digestion begins in your mouth with action of
  your teeth and tongue (mechanical digestion) and
  your salivary glands (chemical digestion).
• The salivary glands produce enzymes that are
  mixed with the food, breaking down the starches.
  Peristalsis is the muscular action that moves the
  food through the esophagus and into your stomach
  after you swallow.

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Your Stomach
The food moves into your stomach, which contains
chemicals such as hydrochloric acid and pepsin.
Pepsin breaks proteins, and other enzymes break
down fat. Your stomach gradually releases these
materials into the upper small intestine
(duodenum), where digestion is completed. Your
stomach also has a thick coating of mucus to
protect it form the acids and to keep it from
digesting itself!
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By the way, your stomach really does look like a
muscular bag!
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Your Liver, Pancreas, and Gall Bladder
Located in the upper portion of your abdomen,
your liver is the largest and heaviest organ of
your body. It is like a busy chemical factory
that plays many roles. For example, your liver
breaks down many substances and toxins, and
produces bile- a substance that helps break down
fat. The bile flows from the liver into the gall
bladder, where it is stored until needed. The
pancreas lies between the stomach and the
duodenum and produces enzymes that flow into the
small intestines, helping to break up complex
starches, proteins, and fats.
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Your Small Large Intestines
After the solid food has been digested the fluid
remaining is called chyme When it is thoroughly
digested it passes through an opening (called the
pylorus sphincter) into the small intestines. In
the small intestines all the nutrients are
absorbed leaving undigestible wastes. These
wastes pass into the large intestines, where
water is removed. Then the wastes are stored in
the rectum until they are released by the anus.
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Cross Section of Your Intestines
The Villi add surface area to increase absorption
of food and nutrients. On the left you see how
the villi line your small intestines, and on the
left you see 1 villi with its capillaries.
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Its a (Intestinal) Gas, Baby!

• The human large intestine, or colon, is home to
  many microorganisms, such as the bacterium
  Escherischia coli (E. coli). Certain foods
  contain large amounts of carbohydrates that our
  digestive enzymes cannot break down.
• When these carbohydrates reach the large
  intestine, our gut microbes respond by "having a
  party (reproducing rapidly, giving off gases
  such as methane and hydrogen sulfide as natural
  by-products of their activities). This is the
  cause of the discomfort and flatulence associated
  with eating beans, cabbage, and other
  gas-promoting foods.
• Fortunately for gas sufferers, the enzymes that
  enable our microbes to break down complex
  carbohydrates are now available in pill form. If
  these are taken before a meal, the enzymes break
  down the carbohydrates in the small intestine so
  that they can be absorbed by the body before they
  reach the hungry throngs of bacteria living in
  the colon.

Web Sources and Resources http//www.colorado.e
du/epob/academics/web_resources/cartoons/gas.html
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DR. I.I.L. MCSNEER PresentsYour Respiratory
System
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The Functions of Your Respiratory System

• Your respiratory system moves oxygen from the
  outside environment into your body. It also
  removes carbon dioxide and water from your body
  (this image shows all the tiny bronchioles that
  carry air into your alveoli for gas exchange).

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The Path of Air
Please label the parts of your respiratory system
on your handout. Can you describe the path that
air takes as it enters and leaves your body?
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Check Your Answers Here.
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How You Breathe 1 The Diaphragm
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How You Breathe 2 The Alveoli
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The Respiratory and Circulatory Systems Working
Together.

• Working together the respiratory and circulatory
  systems form the cario-pulmonary system, which is
  an integral connection between the heart and
  lungs.

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The Cardio-Pulmonary System
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Respiratory Disease Pneumonia

• Pneumonia is an inflammation or infection of the
  lungs most commonly caused by a bacteria or
  virus. Pneumonia can also be caused by inhaling
  vomit or other foreign substances.

Web Sources and Resources www.medimagery.com/Respi
ration/ lungs.html
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Respiratory Disease Lung Cancer
The cancerous lung (right) shows how much damage
smoking can do over time to your respiratory
system.
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X-Rays can help detect cancer, and surgery and
radiation are some treatments for the disease.
Web Sources and Resources www.smm.org/heart/lesson
s/ lesson11.htm
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Please Take Care of Your Lungs and Dont Smoke
Web Sources and Resources Usborne Science
Encyclopedia pgs. and Quicklink Images
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DR. I.I.L. MCSNEER PresentsYour Integumentary
System
(Its Your Skin!)
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Your skin covers your body and prevents the loss
of water. It protects the body from injury and
infection. The skin also helps to regulate body
temperature, eliminate wastes, gather information
about the environment, and produce vitamin D. The
skin is organized into two main layers, the
epidermis and the dermis.
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Can You Name the Parts of Your Skin?
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Skin Anatomy
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What is Botox?
Botox is the commercial name given to a toxin
which is produced from botulism toxin. a medical
protein that is injected into a muscle to cause
temporary (months) paralysis of that muscle. This
helps prevent the appearance of wrinkles.
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With Botox will everyone look the same? What do
you think?
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DR. I.I.L. MCSNEER PresentsYour Immune System
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Your Immune System

• Your Immune system protects you from foreign
  invaders. Special cells react to each kind of
  pathogen with a defense targeted specifically at
  that pathogen.

http//www.nobel.se/medicine/laureates/1996/illpre
s/introduction.html
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Your Immune System Has Many Specialized Cells!

• White blood cells that target specific pathogens
  are called lymphocytes. There are two major kinds
  of lymphocytesT cells and B cells.
• A major function of T cells is to identify
  pathogens by recognizing their antigens. Antigens
  are molecules that the immune system recognizes
  as either part of your body, or as coming from
  outside your body. B cells produce chemicals
  called antibodies.

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How Your Immune System Works

• Our immune system protects us against threats.
  These include viruses, bacteria and parasites
  causing infectious diseases, from ordinary flu to
  full-blown malaria. The white blood cells of the
  defense system are produced in the marrow of our
  bones. The cells are carried in the blood to
  specialized organs, where they develop and
  communicate to launch immune responses against
  infections.
• http//www.nobel.se/medicine/laureates/1996/illpre
  s/introduction.html

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DR. I.I.L. MCSNEER Presents Your Lymphatic
System
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The Functions of Your Lymphatic System

• Your lymphatic system and the cardiovascular
  system are closely related structures that are
  joined by a capillary system. The lymphatic
  system is important to the body's defense
  mechanisms. It filters out organisms that cause
  disease, produces certain white blood cells and
  generates antibodies. It is also important for
  the distribution of fluids and nutrients in the
  body, because it drains excess fluids and protein
  so that tissues do not swell up.

http//www.acm.uiuc.edu/sigbio/project/updated-lym
phatic/node_p2.gif
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DR. I.I.L. MCSNEER Presents Your Muscular System
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Types of Muscles

• Your body has three types of muscle
  tissueskeletal muscle, smooth muscle, and
  cardiac muscle.

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Skeletal Muscle

• Skeletal muscles are attached to the bones of
  your skeleton. Because you have conscious control
  of skeletal muscles, they are classified as
  voluntary muscles. These muscles provide the
  force that moves your bones. Skeletal muscles
  react quickly and tire quickly. At the end of a
  skeletal muscle is a tendon. A tendon is a strong
  connective tissue that attaches muscle to bone.
  Note- ligaments connect bones together.

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Smooth Muscle

• Smooth muscles are called involuntary muscles
  because they work with your conscious effort.

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Cardiac Muscle

• Cardiac muscles are involuntary muscles found
  only in the heart. Cardiac muscles do not get
  tired.

A Cardiac Muscle Cell
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Voluntary Muscles

• The muscles that are under your direct control
  are called voluntary muscles. Smiling and turning
  the pages in a book are actions of voluntary
  muscles

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Involuntary Muscle Action

• The muscles that are not under your conscious
  control are called involuntary muscles. Your
  colon (left) is lined with smooth muscle, and
  your heart (right) is comprised of cardiac muscle
  which works automatically pumping blood around
  your body.

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How Do Muscles Work?

• Muscles work by contracting, or becoming shorter
  and thicker. Because muscle cells can only
  contract, not extend, skeletal muscles must work
  in pairs. While one muscle contracts, the other
  muscle in the pair returns to its original
  length. For example, in order to move the lower
  arm, the biceps muscle on the front of the upper
  arm contracts to bend the elbow. This lifts the
  forearm and hand. As the biceps contracts, the
  triceps on the back of the upper arm returns to
  its original length. To straighten the elbow, the
  triceps muscle contracts while the biceps returns
  to its original length.

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Anatomy Of A Muscle
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Can You Name the Major Muscles of your Body. Try
It!
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Some More Muscles
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Some Major Voluntary Muscles
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Some Really Big Muscles!And on to the
Circulatory System.
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DR. I.I.L. MCSNEER Presents Your Circulatory
System
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Your Circulatory System is Responsible for
Delivering and Removing Materials from Every Cell
in Your Body
Web Sources and Resources Usborne Human Body
Quicklinks
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Blood

• Blood is the fluid of life, transporting oxygen
  from the lungs to body tissue and carbon dioxide
  from body tissue to the lungs.
• Because it contains living cells, blood is alive.
  Red blood cells and white blood cells are
  responsible for nourishing, cleansing, and
  protecting the body. Since the cells are alive,
  they too need nourishment. Vitamins and Minerals
  keep the blood healthy. The blood cells have a
  definite life cycle, just as all living organisms
  do.
• Approximately 55 percent of blood is plasma, a
  straw-colored clear liquid. The liquid plasma
  carries the solid cells and the platelets which
  help blood clot. Without blood platelets, you
  would bleed to death.
• When the human body loses a little bit of blood
  through a minor wound, the platelets cause the
  blood to clot so that the bleeding stops. Because
  new blood is always being made inside of your
  bones, the body can replace the lost blood. When
  the human body loses a lot of blood through a
  major wound, that blood has to be replaced
  through a blood transfusion from other people.

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Can You Name The Major Parts of Your Heart and
Trace Its Blood Flow? Try It.
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Now Check To See How You Did.
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Heart Dissections

• Your Heart is a Very Muscular Organ!

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Artificial Hearts

• The action of the artificial heart is entirely
  similar to the action of the natural heart. There
  is, however, one huge difference the natural
  heart is living muscle, while the artificial
  heart is plastic, aluminum, and Dacron polyester.
  As a result, the artificial heart needs some
  external source of "life." An external power
  system energizes and regulates the pump through a
  system of compressed air hoses that enter the
  heart through the chest. Since the system is
  cumbersome and open to infection, the use of an
  artificial heart is meant to be temporary.
• http//sln.fi.edu/biosci/healthy/fake.html

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Now Its On To Your Skeletal System
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DR. I.I.L. MCSNEER Presents Your Skeletal System
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Your Skeletons Functions

• Your skeleton has five major functions. It
  provides shape and support, enables you to move,
  protects your internal organs, produces blood
  cells, and stores certain materials until your
  body needs them

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The Structure of Bone

• Many bones have the same basic structure. A thin,
  tough membrane covers all of a bone except the
  ends. Blood vessels and nerves enter and leave
  the bone through the membrane. Beneath the
  membrane is a layer of compact bone, which is
  hard and dense, but not solid. Small canals run
  through the compact bone, carrying blood vessels
  and nerves from the bones surface to the living
  cells within the bone. Just inside the compact
  bone is a layer of spongy bone, which has many
  small spaces within it.

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Bone Anatomy
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Cartilage

• Cartilage provides a smooth surface between bones
  or sometimes a more flexible extension of bone,
  as in the tip of your nose. As an infant, much of
  your skeleton was cartilage. By the time you stop
  growing, most of the cartilage will have been
  replaced with hard bone tissue.

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Joints

• A joint is a place in the body where two bones
  come together. Joints allow bones to move in
  different ways. Immovable joints connect bones in
  a way that allows little or no movement. Movable
  joints allow the body to make a wide range of
  movements. Movable joints include ball-and-
  socket joints, pivot joints, hinge joints, and
  gliding joints. The bones in movable joints are
  held together by a strong connective tissue
  called a ligament.

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Take Care of Your Bones!

• A combination of a balanced diet and regular
  exercise can start you on the way to a lifetime
  of healthy bones. As people become older, their
  bones begin to lose some minerals. Mineral loss
  can lead to osteoporosis, a condition in which
  the bodys bones become weak and break easily.
  Regular exercise and a diet rich in calcium can
  help prevent osteoporosis.

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Do You Know Your Bones?

• Fill in the blanks on the next slide or on your
  handout, and check the following slide for the
  answers.

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Test Your Knowledge
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How Did You Do?
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Osteoporosis

• Osteoporosis is a disease in which bones become
  fragile and more likely to break. If not
  prevented or if left untreated, osteoporosis can
  progress painlessly until a bone breaks.

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Its on to the Nervous System
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DR. I.I.L. MCSNEER Presents Your Nervous System

• Your nervous system receives information about
  what is happening both inside and outside your
  body. It also directs the way in which your body
  responds to this information. In addition, the
  nervous system helps maintain homeostasis. A
  stimulus is any change or signal in the
  environment that can make an organism react

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Your Nervous System

• Your nervous system consists of the central and
  peripheral systems. The central nervous system
  (CNS), includes the brain and spinal cord the
  peripheral system includes the nerves to the rest
  of the body.

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What Is Homeostasis?

• Homeostasis and Negative Feedback
• Homeostasis is one of the fundamental
  characteristics of living things. It refers to
  the maintenance of the internal environment
  within tolerable limits. All sorts of factors
  affect the suitability of our body fluids to
  sustain life these include properties like
  temperature, salinity, acidity, and the
  concentrations of nutrients and wastes. Because
  these properties affect the chemical reactions
  that keep us alive, we have built-in
  physiological mechanisms to maintain them at
  desirable levels. When a change occurs in the
  body, there are two general ways that the body
  can respond. In negative feedback, the body
  responds in such a way as to reverse the
  direction of change. Because this tends to keep
  things constant, it allows us to maintain
  homeostasis. On the other hand, positive feedback
  is also possible. This means that if a change
  occurs in some variable, the response is to
  change that variable even more in the same
  direction. This has a de-stabilizing effect, so
  it does not result in homeostasis. Positive
  feedback is used in certain situations where
  rapid change is desirable (see Positive Feedback
  for an example).
• To illustrate the components involved in negative
  feedback, we can use the example of a driver
  trying to stay near the speed limit. The desired
  value of a variable is called the set point.
  Here, the set point is a speed of 55 mph in
  controlling body temperature, the set point would
  be 98.6 degrees. The control center is what
  monitors the variable and compares it with the
  set point. Here, the control center is the
  driver for body temperature, it would be the
  hypothalamus of the brain. If the variable
  differs from the set point, the control center
  uses effectors to reverse the change. Here, the
  effector is the foot on the accelerator pedal in
  controlling body temperature, it would include
  the glands that sweat and the muscles that
  shiver.

Web Sources and Resources http//www.colorado.ed
u/epob/academics/web_resources/cartoons/gas.html
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Neurons

• The cells that carry information through your
  nervous system are called neurons, or nerve
  cells. The message that a neuron carries is
  called a nerve impulse. A neuron has a large cell
  body that contains the nucleus. The cell body has
  threadlike extensions. One kind of extension, a
  dendrite, carries impulses toward the cell body.
  An axon carries impulses away from the cell body.
  Axons and dendrites are sometimes called nerve
  fibers. A bundle of nerve fibers is called a
  nerve.

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The Anatomy of a Neuron
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A NEURON viewed under a electron microscope. Can
you locate the cell body, axon, and dendrites?
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Your Central Nervous System- The Brain and Spinal
Cord
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Central Peripheral Nervous Systems Working
Together

• The yellow parts are CNS parts and the purple are
  parts of your peripheral nervous system.

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Reflexes Some nerve signals go only to the
spinal cord and back.
The knee jerk reflex (seen in the figure to the
above) is called a monosynaptic reflex. This
means that there is only 1 synapse in the neural
circuit needed to complete the reflex. It only
takes about 50 milliseconds of time between the
tap and the start of the leg kick...that is fast.
The tap below the knee causes the thigh muscle to
stretch. Information is sent to the spinal cord.
After one synapse in the ventral horn of the
spinal cord, the information is sent back out to
the muscle...and there you have the reflex.
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Your Brain- The Command Center

• The human brain is a complex organ that allows
  us to think, move, feel, see, hear, taste, and
  smell. It controls our body, receives
  information, analyzes information, and stores
  information (our memories).
• The brain produces electrical signals, which,
  together with chemical reactions, let the parts
  of the body communicate. Nerves send these
  signals throughout the body.
• The average human brain weighs about 3 pounds. At
  birth, the human brain weighs less than a pound.
  As a child grows, the number of cell remains
  relatively stable, but the cells grow in size and
  the number of connections increases. The human
  brain reaches its full size at about 6 years of
  age.

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Most nerve signals are interpreted by your brain
and motor nerves then carry out your instructions.
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The Stroop Effect- Your Brain Can Get Confused!

• TRY IT!- The famous "Stroop Effect" is named
  after J. Ridley Stroop who discovered this
  strange phenomenon in the 1930s. Here is your
  job name the colors of the following words. Do
  NOT read the words...rather, say the color of the
  words. For example, for the word BLUE, you should
  say "RED". Say the colors as fast as you can. It
  is not as easy as you might think!

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Major Brain Sections
cerebrum
cerebellum
brain stem
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Your Brain Has Very Complicated Anatomy All Its
Own!
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Alzheimers Disease

• Alzheimer's disease attacks the brain it is not
  a normal part of aging. People with AD have a
  gradual memory loss and difficulties with
  language and emotions.
• The progressive loss of intellectual abilities is
  termed dementia. As the disease advances, the
  person may need help in all aspects of life
  bathing, eating, and using the restroom.
• Because of this round-the-clock care, families
  and friends of people with AD are greatly
  affected. The disease is irreversible and there
  is currently no cure.

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Ouch! In the movie MATRIX, Neo and the others
are plugged into the matrix through their CNS
!(Central Nervous System)
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Your Senses Are Your Nervous Systems Bridge to
the Outside World
Sight, Taste, Touch, Hearing, Smell
Web Sources and Resources Usborne Science
Encyclopedia pgs. 370-375 and Quicklink Images
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Quick Quiz

• How well do you know your own nervous system?
  Fill in the blanks on the slides that follow.
  Then go back and check your work if needed.

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(No Transcript)
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(No Transcript)
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Which Way Does The Impulse Travel?
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DR. I.I.L. MCSNEER Presents Your Endocrine
System

• The endocrine system is a collection of special
  organs in the body that produce hormones. These
  organs are usually called the "glands." They are
  located in different parts of the body. For
  example, the pituitary is in the brain, the
  thyroid is in the neck, the adrenal glands are
  just alone the kidneys and the sexual glands
  (ovaries and testes) are located in the sexual
  organs. Each gland produces a hormone into the
  blood, which travels all through the body.
  Hormones regulate our body activities, for
  example growth, sleep, sudden actions, feelings
  and blood sugar for energy.

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DR. I.I.L. MCSNEER Presents Your Excretory
System

• Your excretory system collects wastes produced by
  cells and removes these wastes from your body.
  The removal process is known as excretion. The
  two kidneys are the major organs of the excretory
  system. The kidneys filter your blood and remove
  urea, excess water, and some other waste
  materials from your blood. Urea is a chemical
  that comes from the breakdown of proteins. The
  filtering process produces a watery fluid called
  urine. Each kidney contains about a million
  nephrons.

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Your Excretory System
Web Sources and Resources Usborne Science
Encyclopedia pg. 362 and Quicklink Images
107
Kidney Tubules (Nephrons)
Urine Production The kidneys regulate the body
fluids, maintaining desirable levels of acids and
bases, salts, nutrients and wastes. Each kidney
is made up of over a million tiny tubes known as
nephrons, or kidney tubules. The tubules act in
parallel to filter the blood and produce the
urine. As the blood filtrate passes along the
tubule, the composition of the fluid is changed
in complex ways. In some ways the tubule
resembles an industrial processing plant, and the
cells lining the walls of the tubule can be
thought of as technicians who modify the filtrate
as it passes by. The first step in urine
production is called filtration. This occurs at
the glomerulus, which is really a ball of
capillaries that makes close contact with the end
of the nephron. Driven by the beating of the
heart, blood plasma (the fluid component of
blood) is forced out of the capillaries and into
the nephron. Because this transfer occurs through
narrow spaces (represented by a sieve in the
cartoon), the larger molecules (mainly proteins)
are left behind in the blood. Blood cells (not
shown in the cartoon) are many times larger
still, and are also left behind. Finally, the
tubule empties its contents into one of the many
collecting ducts. The urine now contains a
concentrated solution of whatever the body
currently considers to be "wastes." Water
continues to be reabsorbed in the collecting
duct, so that little water is wasted in the
process of excretion (elimination of wastes).
Finally, all the urine collects together in the
kidney and is passed out through the ureter, and
from there to the bladder.
Web Sources and Resourceshttp//www.colorado.edu/
epob/academics/web_resources/cartoons/gas.html
108
Kidney Stones

• Kidney stones are created when certain substances
  in urine -- including calcium and uric acid --
  crystallize and the crystals clump together.
  Usually, they form in the center of the kidney,
  where urine collects before flowing into the
  ureter, the tube that leads to the bladder. Small
  stones are able to pass out of the body in the
  urine and often go completely unnoticed. But
  larger stones irritate and stretch the ureter as
  they move toward the bladder, causing
  excruciating pain and blocking the flow of urine.
  Rarely, a stone can be as large as a golf ball,
  in which case it remains lodged in the kidney,
  creating a more serious condition

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DR. I.I.L. MCSNEER Presents Your Reproductive
System
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The Female Reproductive System

• The role of the female reproductive system is to
  produce eggs, and if an egg is fertilized, to
  nourish a developing baby until birth.

111
The Menstrual Cycle

• During the menstrual cycle, an egg develops in an
  ovary. At the same time, the uterus prepares for
  the arrival of the fertilized egg. Once the egg
  is released, it can be fertilized for the next
  few days if sperm are present in the oviduct. If
  the egg is not fertilized, it begins to break
  down, and it passes out of the vagina along with
  some tissue from the lining of the uterus in a
  process called menstruation.

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Can you name the parts of the female reproductive
system? Check your answers on the following page.
113
Key to the Female Reproductive System
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The Male Reproductive System

• Produces sperm- tiny packages of chromosomes that
  can swim to fertilize the egg, and the hormone
  testosterone, which controls the development of
  the males physical characteristics.

115
Can you name the parts of the male reproductive
system? Check your answers on the following page.
116
Key to Male Reproductive System
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Fertilization

• Takes place when sperm egg merge.

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Human Development

• The fertilized egg, or zygote, is about the size
  of a period in your textbook. The zygote develops
  into an embryo, and then into a developing fetus,
  which results in....

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You!
www.ajwrb.org/images/ fetus.jpg
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Thank You For Visiting Human Body Systems by DR.
I.I.L. MCSNEER!
121
Try These Sites for More InfoNote if they dont
work by clicking on them, just type the address
into your browser.

• A Look Inside the Human Body http//www4.tpgi.com.
  au/users/amcgann/body/
• MY BODY FOR KIDS http//www.kidshealth.org/kid/bod
  y/mybody.html
• Find out how your body works! http//yucky.kids.di
  scovery.com/noflash/body/index.html
• Take and Anatomy Quiz at the Smithsonian
  http//americanhistory.si.edu/anatomy/bodyparts/nm
  a03_bodyparts.html
• Hillendale Health Site- Learn About Your Body
  http//hes.ucf.k12.pa.us/gclaypo/health_index.html