Download 5 circulatorysystem - Teacher Geeks

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Learning About the Circulatory System
What’s In Your Blood?
If you drained out all your blood, you could fill a 5-liter
bucket. Every cell in your body depends on blood to deliver food
and oxygen and to carry away wastes. Blood is the key to keeping
all the cells of your body alive. There are four components to the
blood: plasma, red blood cells, white blood cells and platelets.
The plasma is mostly water and its function is to carry all the
other components through the body. It is pale yellow and contains
some sugar, protein, minerals and waste materials. The platelet’s
function is to keep you from bleeding to death by making a clot
(we call it a scab) and keeping the blood from flowing out a cut.
They are about 1/3 the size of red blood cells, live for 7 – 9 days,
and are produced in the bone marrow.
You have about 15 trillion red blood cells (RBC). The
function of the RBC is to transport the oxygen from the lungs to
the cells. They are mostly made of hemoglobin, which is an ironcontaining protein that binds chemically to oxygen molecules. RBC
do not have a nucleus so they can only live about 120 days.
The function of the white blood cells (WBC) is to attack
germs and other invaders that get into the body. Some white blood
cells recognize disease-causing organisms and others produce
chemicals to fight the invaders. WBC differ from RBC in several
ways. There are fewer of them – 1 WBC for every 500 to 1,000
RBC’s. They are much bigger than RBC, have a nucleus, and can
live for months or even years.
Fun facts about the Circulatory System
 Every second about 2 million red blood cells die.
 Your heart pumps about 4,000 gallons of blood each day.
 It takes about 1 minute for the blood to circulate throughout your
body.
 An average human’s heart beats 30 million times per year.
 The sound of a heartbeat is created by the valves in the heart closing
as they push blood through its chambers.
 There are 5 million red blood cells, 10,000 white cells and 250,000
platelets in a pinhead-size drop of blood.
Materials: colored pencils, model of
the blood
What To Do:
1. Look at the diagram of the blood.
2. The red blood cells look like donuts.
Color them red.
3. The white blood cells are larger than
the red cells. Don’t color them
4. The platelets are very small and are
clear in the blood. Color them purple.
5. Color the plasma around the blood cells yellow.
Scientists use models and pictures to represent ideas and objects
too big or too small to see with the unaided eye. The microscope
aids our eyes in seeing very small things and the telescope aids our
eyes to observe objects that are very far away. When we use
models there are problems with size, scale, color and materials.
These problems are called limitations.
Questions:
1. What is a limitation of the model of blood we used?
________________________________________________
2. What is a limitation of the picture we used?
________________________________________________
Why does your blood look blue/green?
Some people think that the blood inside them is blue. That is not
true. You have RED blood cells not blue. This is what happens.
Your skin is thin and acts like a filter. Typical light has all the
colors of the rainbow in it. When light goes through your skin and
hits the blood vessels it bounces back out but the red is filtered by
your skin leaving only the blue and yellow from the rainbow. This
blue/green color is what we see.
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Color in the diagram as your teacher does on the overhead.
Materials: ½ straw with red water, clay, petri dish, milk
What To Do:
1. Your teacher will show you ½ a straw that has been
filled with red food coloring.
2. Your teacher will place it in the petri dish and begin
covering it with milk.
3. Observe the color of the straw when covered with milk.
Questions:
1. What color do you observe the straw to have? ________
2. What made it change color? ______________________
_____________________________________________
3. What does the milk represent? ____________________
4. Why do you see a different color than red? ___________
_____________________________________________
 Your heart will be red.
 Your arteries will also be red as they carry oxygen rich blood
away from your heart.
 Your veins will be blue as they carry oxygen poor blood
(carbon dioxide rich) back to your heart.
Listening to Our Hearts
Your heart is mostly muscle tissue. It has only one function. Day
and night, twenty-four hours a day, your heart pumps blood to
every part of your body. Your circulatory system functions to help
control your temperature, to fight disease, to carry oxygen,
nutrients, and water to your cells, and to carry away waste from
your cells. Every time your heart beats, the blood is being squeezed
out of the heart, into an artery and out to the body. The arteries
take the blood away from the heart where they connect with the
smallest blood vessels called capillaries. Capillaries are
microscopic blood vessels that allow materials to pass through
them to the cells by diffusion. The capillaries connect with the
veins, which take the blood back to the heart.
Label the diagram with the
following words.
1. Heart
3. Artery
2. Vein
4. Capillary
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Materials: stethoscope, alcohol, cotton balls
What To Do:
1. Clean the earpiece of the stethoscope with alcohol and a cotton
ball.
2. Use the stethoscope to listen to your heart.
3. Listen for two different sounds.
4. Doctors call the sounds the “LUB” and “DUB.” See if you can
hear them.
5. A LUB and a DUB make one heartbeat.
6. Switch with your partner so they can listen to their heartbeat.
Questions:
1. What is the function of the heart? __________________________
2. What sounds does the heart make? _________________________
3. Why is blood such an essential fluid to the circulatory and
respiratory systems?
_______________________________________________________
_______________________________________________________
4. How do arteries differ from veins? ________________________
_______________________________________________________
5. How does the function of capillaries fit into the circulatory
system?_________________________________________________
_______________________________________________________
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Name _________________period _____ date______
EXIT TICKET - Circulatory System
1. What color is your blood?
A. blue
B. yellow
C. green
D. red
2. What is the function of the circulatory system?
A. Deliver food to your cells
B. Take wastes away from your cells
C. Take oxygen to your cells
D. All of the above
3. What is a limitation of a model?
A. A grade
B. A problem in size or scale
C. The builder of the model
D. All the correct things found on the model
Conclusion:
Red blood cells carry the ____________ to all cells of the
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Name _________________period _____date______
EXIT TICKET- Circulatory System
1. What is the function of the circulatory system?
A. Deliver food to your cells
B. Take wastes away from your cells
C. Take oxygen to your cells
D. All of the above
2. What color is your blood?
A. blue
B. yellow
C. green
D. red
3. What is a limitation of a model?
A. A grade
B. A problem in size or scale
C. The builder of the model
D. All the correct things found on the model
body. __________ blood cells attack invaders.
Conclusion: (blood, platelets, oxygen, white, plasma)
Red blood cells carry the _________ to all cells of the body.
____________ is the liquid that carries all the other
_______ blood cells attack invaders. ________ is the liquid
components of blood. The component of the blood that
that carries all the other parts of blood. The component of
causes it to clot is the ____________.
the blood that causes it to clot is the ____________.