Download Your heart pumps and circulates blood to every part of your body so

heart
CIRCULATION IN
YOUR HEART! Design
+ build + operate an
artificial heart.
Your heart pumps and circulates blood to every part of your body so
that all of your cells get the oxygen and nutrients they need to survive. In a single day, your heart can pump about 1,000-2,500 gallons
of blood. To keep you alive, your heart works without any breaks or
rests! But, unfortunately, the heart is not indestructible. People can
suffer from the break down or weakening of the heart, or they can be
born with a weaker heart. This can result in heart failure, where the
heart can no longer pump enough blood for the body's needs.
In the most severe cases of heart failure, the only long term solution is to replace the heart. For many years the only way to replace
a heart was through a transplant, where a failing heart is replaced
with a living heart from an organ donor. Since this process was, for
many reasons, very difficult, more recently, doctors, scientists, and
engineers have come up with another transplant option: an artificial
heart!
Making an artificial heart was very hard because it was trying to take
the place of something very complex. There are four chambers in
your heart, and each one has a specific job to do to make sure your
body has enough oxygen. Blood comes into the right atrium from
the body. This blood is low in oxygen and high in carbon dioxide.
Blood is then pumped into the right ventricle and the next stop is the
lungs to drop off the carbon dioxide and pick up more oxygen. From
the lungs the blood is pumped back to the left atrium and then on to
the left ventricle which finally pumps the blood back into your body.
An artificial heart has to be designed to do the job of each original
chamber correctly. That's tough to do! On top of that, an artificial
heart needs a new power source. A real human heart is made of
muscle, and just like the muscles in your arms and legs, the heart
depends on the food you eat to give it the energy it needs to pump
blood, but an artificially heart can't use the food you eat.
There are several artificial hearts that exist, but they too have some
issues such as size, weight, and attachments.
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MAKING MACHINES out of paper and sticks
JARVIK 7 was the first artificial heart used in people 1982. This heart
has only two pumps which replace the two lower chambers of a
person's heart that has stopped working. The power system for this
heart is large and bulky and it connects to the pumps through tubes
that poke through the skin – ouch!
ABIOCOR, a more recent version, has a mechanical pump which
completely replaces the pumping action of the lower chambers of
a person's heart. It allows doctors to completely remove a person’s
heart and replace it with a whole new system. The difficulty with this
model is that a lot of equipment has to be placed inside the body.
The equipment is bulky and puts a lot of pressure on the other
organs.
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collect
PLASTIC TUBING
FOUR SMALL PLASTIC BOTTLES
FOOD COLORING
THICK STRAWS
THIN STRAWS
SCISSORS
TAPE
BALLOONS
experiment
1. Draw a diagram of the four chambers of the heart and how they
connect to each other to use as an organizational guide. You will
use the plastic bottles to represent these chambers.
2. Take the four bottles and make holes in each of the caps, big
enough to fit the tubing.
3. Tape two bottles together with the cap sides touching. Do the
same with the two remaining bottles.
4. Take a sharp pencil or scissors and make a hole at the bottom of
the first two bottles that represent the upper chambers of the
heart and two holes on the top of the bottles that will represent
the lower chambers of the heart.
5. Use the clear tubing to connect the top bottles to the bottom
bottles through the holes made. The bottom bottle should have
the rubber tubing touching the bottom of the lower bottle so
that when the bottom bottle is squeezed water will flow up the
tube and pour water into the top bottle.
6. Remember to put valves in the caps of the bottom bottle so that
no water is leaking back up to the top bottle when the bottom
is squeezed. Do this for the other side two in order to complete
your four chambered heart.
reflect
What can you change about your four chambered heart to
make it pump better? What would happen if you only had a
three chambered heart? Where would the blood from the top
chamber go? Why does the heart need a left and right side?
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MAKING MACHINES out of paper and sticks