most of these slides were created by h. leonard modified by e. anderson 1 body blitz an overview of...

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Most of these slides were created by H. Leonard modified by E. Anderson 1 Body Blitz an overview of human body systems

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Page 1: Most of these slides were created by H. Leonard modified by E. Anderson 1 Body Blitz an overview of human body systems

• Most of these slides were created by H. Leonard

• modified by E. Anderson

1

Body Blitzan overview of human body systems

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In addition to this slide show, study HBS 1-page Review

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HBS 1 Page Review record # __ HBS 1 Page Review record # __

LEVELS of ORGANIZATION (from simplest to most complex) Cells --> Tissues --> Organs --> Organ Systems HOMEOSTASIS: staying the same--tendency of the body to maintain a stable, balanced internal environment, e.g. not too hot or cold. REGULATION: how your body keeps homeostasis—self-regulating adjustments, e.g. sweats when getting hot, shivers when getting cold.

ORGAN SYSTEMS

1. Integumentary

Description: Body covering. Skin, hair, nails, sweat glands. Function: protect underlying tissues and regulate body temperature

largest organ of the body Perspiration (sweat) cools body when water evaporates from skin.

2. Skeletal

Description: Bones, ligaments, cartilage Function: Support, movement, protection, and production of blood cells

Bones are ALIVE. Help in movement and support, also protection Blood cells are made in bone marrow

3. Muscular

Description: Muscles of the body Function: Movement, maintenance of posture, production of body heat

Voluntary muscles are connected to bones (skeletal) Muscles of internal organs are not connected to skeleton Actively contract (shorten), passively relax (lengthen) Brain sends nerve signals to control movement Skeletal muscles help pump blood back to the heart.

4. Nervous

Description: Brain, spinal cord, nerves through the body Function: Communication throughout body, mental activities, maintaining homeostasis

Brain is control center of all body activities Sends and receives signals to and from body Neuron = nerve cell made of axon, dendrites, terminal branches, cell body Nerve is an organized bunch of neurons Some nerves bring signals from sensors (e.g. touch or heat or light) to brain; other nerves send signals from brain or

spinal cord to muscles. Synapse is a gap between neurons.

5. Endocrine Description: Ductless glands, e.g. pituitary, adrenal, thyroid, parathyroid, pancreas, ovaries, testes, thymus Function: Secretion of hormones, chemical communication between body parts

6. Digestive

Description: Mouth, teeth, pharynx, esophagus, stomach, small intestine, large intestine, liver, gall bladder, and many glands including the pancreas Function: Breakdown of food into molecules that can be absorbed by blood.

Mechanical digestion: teeth/ stomach muscles Chemical digestion: saliva/ stomach acids/ enzymes of small intestine Most food absorption is from the small intestine (After absorption, blood vessels carry blood with nutrients to body parts) In large intestine (colon), water is reabsorbed Stomach is lined with mucus to protect from acid damage Peristalsis- movement of food by muscles in esophagus

Large intestine: absorbs too much water = constipation absorbs too little water = diarrhea Solid waste removal Anus is the muscle that opens to let out feces. (NOT the excretory system)

7. Circulatory = Cardiovascular

Description: Heart, blood vessels, blood. Function: Transports materials throughout the body.

Movement of oxygen, nutrients, and wastes throughout body You should know the cyclical path of blood:

o from heart, pushed to lung to pick up oxygen and drop off CO2, turns RED, o returns to heart, pumped to the rest of body where it drops off oxygen and picks up CO2 and turns BLUE, o then returns to the heart to start cycle again.

8. Excretory = Urinary

Description: Kidneys, ureters, urinary bladder, urethra Function: Removes (filters) wastes from the blood and helps maintain the body's water and electrolyte balance

Kidney is a filter system Wastes = Carbon dioxide, water, urea liquid waste removal

9. Reproductive Description: Reproductive organs, primarily the ovaries (females) and testes (males) Function: Produce special reproductive cells for reproduction

10. Respiratory Description: Nose, mouth, trachea, bronchi, LUNGS, alveoli Function: Brings O2 to the blood, takes CO2 away from blood.

Takes in oxygen, gives off carbon dioxide (gas exchange)

11. Immune Description: Includes skin, white blood cells Function: Blocks and fights off invaders like bacteria and viruses

3 points of attack: barriers, general inflammatory response, and specific immune response (T and B cells)

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What is a system?

• An organized collection of parts that function together to do something greater than all the separate parts could do.

• Examples: a toaster, ...

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

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

• And Levels of Organization

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Human Body Systems

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This slide presentation is meant to help you study the major systems of the human body.

You can find a copy in the Human Body Systems section of my website.

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 skip to focus on any one system.

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http://www.parentingpress.com/pics/sock_cvr.jpg

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

Believe it or not, you are organized!

At least your body is.

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How can you access and use this slide presentation? What are the 4 levels of organization shown here?

1

3

2

4

Predict the next lower level and the next higher.

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Levels of Organization The Human Body has several “layers” of organization beginning with the

simplest and becoming more complex.

8http://www.bmb.psu.edu/courses/bisci004a/chem/levels.jpg

Answers to previous slide: 1cell, 2tissue, 3organ (small intestine), 4organ system.

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Here They Are: Your Body Systems (Part 1).

9http://www.agen.ufl.edu/~chyn/age2062/lect/lect_19/147a.gif

• (musculoskeletal) (hormone) (cardiovascular)

Don’t blush; it’s only skin!

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http://www.agen.ufl.edu/~chyn/age2062/lect/lect_19/lect_19.htm

Your Body Systems (Part 2)

• =excretory

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DR. I.I.L. MCSNEER Presents…

Your Digestive System

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What does your digestive system do? (3 functions)

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1... breaks down food into molecules the body can absorb.2…passes these molecules into the blood to be carried throughout the body.3…eliminates solid wastes from the body.

Your Digestive System is an efficient disassembly line.

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Parts of Your Digestive System

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mouth•What do the parts add up to?

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Now for the Digestive Journey

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Cross Section of your small intestine

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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 right you see 1 villus with its blood

capillaries.

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Why is a large surface area important?

• Chemistry happens when surfaces contact.– Think of examples.

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Where does the gas come from?

•We don’t digest food completely by ourselves.•Bacteria and fungi live in our intestines and digest the rest for us, as well as for themselves! (E. coli, for example)•These microbes that we depend on have their own wastes, e.g. methane and hydrogen sulfide.

18Web Sources and Resources: http://www.colorado.edu/epob/academics/web_resources/cartoons/gas.html

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DR. I.I.L. MCSNEER Presents…

Your Respiratory System

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What does your respiratory system do?

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•takes in air from outside your body

–removes some oxygen to give to your body–adds carbon dioxide and water (wastes from your body)

•sends out the altered air•This image shows all the tiny bronchioles that increase surface area in the alveoli for gas exchange.

•Why is high surface area important?•C H A S

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• mouth and nose• trachea• bronchi• alveoli• blood• organs• blood• alveoli• bronchi• trachea• mouth and nose

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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.

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How The Circulatory and Respiratory Systems Work Together

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Respiratory Disease: Pneumonia

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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 Resourceswww.medimagery.com/Respiration/ lungs.html

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Effects of smoking: black gummy build-up, increased chance of lung cancer

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non-smoker smoker

There are MANY forms of cancer, some deadly, others not so dangerous.

Please note that not all cancers are caused by bad habits.

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X-Rays can help detect lung cancer.Surgery, radiation, and drugs (chemotherapy)

are some treatments for the disease.

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Web Sources and Resources

www.smm.org/heart/lessons/ lesson11.htm

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Web Sources and Resources:

Usborne Science Encyclopedia pgs. and Quicklink Images

Please Take Care of Your Lungs and Don’t Smoke

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DR. I.I.L. MCSNEER Presents…

Your Integumentary System

30(It’s Your Skin!)

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What does skin do?

• prevents the loss of water• protects the body from

injury and infection• regulates body temperature• eliminates wastes• gathers information about

the environment• produces vitamin D

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Parts of Your Skin

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Skin Anatomy

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What is Botox?

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• a protein from botulism toxin

• injected into a muscle to cause temporary (months) paralysis

• 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 Presents…

Your Immune System

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What does your immune system do?What are some of its parts?

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•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/illpres/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 lymphocytes—T 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

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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/illpres/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.

41http://www.acm.uiuc.edu/sigbio/project/updated-lymphatic/node_p2.gif

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DR. I.I.L. MCSNEER Presents… Your Muscular System

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What are the types of muscle tissue?

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Your body has three types of muscle tissue—skeletal muscle, smooth muscle, and cardiac muscle.

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Skeletal Muscle

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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

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

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Cardiac Muscle

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Cardiac muscles are involuntary muscles found only in the heart. Cardiac muscles are strong but do not tire easily.

A Cardiac Muscle Cell

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Voluntary Muscles

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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

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•colon(smooth muscle)

•heart(special cardiac muscle)

•both involuntary•(automatic) •not under your conscious control

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How Do Muscles Work?

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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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skeletal muscles

striated,voluntary

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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= Cardiovascular System

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Your Circulatory System is Responsible for Delivering and Removing Materials from Every Cell in Your Body

55Web Sources and Resources Usborne Human Body: Quicklinks

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Blood

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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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.

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Heart Dissections

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Your Heart is a Very Muscular Organ!

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Artificial Hearts

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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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Cardiovascular = Circulatory

Next up: Your Skeletal System 60

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DR. I.I.L. MCSNEER Presents…

Your Skeletal System

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What are your skeleton’s functions?

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1. provides shape and support

2. enables you to move3. protects your

internal organs4. produces blood cells5. stores certain

materials until your body needs them

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The Structure of Bone

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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 bone’s 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

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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

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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!

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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 body’s 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?

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What is osteoporosis?

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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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It’s on to the Nervous System

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DR. I.I.L. MCSNEER Presents…

Your Nervous System

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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 SystemYour 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 FeedbackHomeostasis 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.

ADJUSTING TO STAY WITHIN LIMITS

74Web Sources and Resources: http://www.colorado.edu/epob/academics/web_resources/cartoons/gas.html

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What are neurons?

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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.

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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

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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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Page 84: Most of these slides were created by H. Leonard modified by E. Anderson 1 Body Blitz an overview of human body systems

Where are the major 3 brain sections?

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cerebrum

cerebellum

brain stem

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Your Brain Has Very Complicated Anatomy All Its Own!

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Page 86: Most of these slides were created by H. Leonard modified by E. Anderson 1 Body Blitz an overview of human body systems

Alzheimer’s Disease

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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 System’s Bridge to the Outside World

88Web Sources and Resources: Usborne Science Encyclopedia pgs. 370-375 and Quicklink Images

Sight, Taste, Touch, Hearing, Smell

What are the five senses?

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DR. I.I.L. MCSNEER Presents…

Your Endocrine System

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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 = Urinary System

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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(also called Urinary System)

91Web Sources and Resources:

Usborne Science Encyclopedia pg. 362 and Quicklink Images

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Kidney Tubules (Nephrons)

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Urine ProductionThe 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 Resources:http://www.colorado.edu/epob/academics/web_resources/cartoons/gas.html

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Kidney Stones

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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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Slides to be added

• Themes and terms:• mechanical• chemical• surface area• peristalsis• coordinate (verb)• absorb• villi

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