The Circulatory System

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(No Transcript)
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The Circulatory System
YO! My heart is beating with excitement to teach
you about the circulatory system!
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1 A reminder of systems
As we go through this presentation about the
circulatory system, dont forget what a system is
in the first place.
A body system is a collection of structures that
each have their own function that work together
to do certain tasks.
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2 Function, Structure Disorders
As we go through our study of how the human body
works, studying each system one at a time, youll
get used to us discussing

• Structures of the system in other words, the
  parts organs
• Functions of the system these are the jobs of
  the system
• Disorders of the system common diseases or
  problems that
• affect the system
• Joes anatomy health. We need SOMEBODY to be
  our victim.

Say what?
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3 Homeostasis Response to Stimuli
You know how a volcano quits erupting when it
runs out of kinetic energy? It reaches a
point called equilibrium, where all the pressure
pushing upwards is equal to the pressure of rock
pushing downward.
Your body needs to be in equilibrium, too. This
is called homeostasis. Homeostasis refers to the
idea that your body is within normal operating
conditionsnot too hot, not too cold, not too
salty, not too anything. Homeostasis is BALANCE.
?
Your body responds to stimuli, too. A stimulus
is anything that causes a response from your
body. Internal stimuli are within the body,
while external stimuli are from outside your body.
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4 Circulatory System Overview
The circulatory system is the network of heart
and vessels moving blood through the body
The mileage of vessels you have in your body is
ridiculous. Laid end-to- end, your blood vessels
would easily circle the Earth.
Whoa.
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5 FUNCTIONS of the Circulatory System
Remember, when you see the word function, just
think JOB.

• Carries nutrients to cells from digested food

2. Carries oxygen to cells from inhaled air
3. Carries wastes from cells to kidneys lungs.
4. Fights diseases
So it looks like theres a lot of carrying
going on. Think of the circulatory system being
like the highways roadsthey let important
stuff get from here to there inside your body.
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6 STRUCTURE No.1The Heart
You normally dont notice your heart at work.
Only after youve run a mile or seen your crush
walk past you down the hallway do you seem to
notice it at all. But its always at work,
constantly pumping blood through your vessels.
(Joe needs some thickness)
Lets clear up some misconceptions
The heart doesnt look like a Valentine
And its not off to the left in your chestits
right in the middle. Because its slightly tilted
and strongest on the left, it tricks us where
its location truly is.
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7 Heart, continued
The heart is made of cardiac muscle, and has 4
chambers.
Well, this is tricky to draw Instead, draw a
normal heart shape, divide it into fourths, and
number them as such
1
3
2
4
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8 Heart, continued
Lets see what these different chambers are do.
1
3

• Left atrium receives high O2 blood from lungs
• Left ventricle pumps high O2 blood to body
• Right atrium receives low O2 blood from body
• Right ventricle pumps low O2 blood to lungs

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4
If you trace through what is going on here,
youll see that the heart receives pumps blood
through two loopsone loop sends blood to the
lungs to freshen up with oxygen, the other loop
sends blood to the body so cells can grab at
that oxygen. TWO LOOPS!
Pulmonary Circulation
Systemic Circulation
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9 STRUCTURE No.2Blood Vessels
If we compare your circulatory system to a system
of highways roads, then Im not quite sure
what the heart would be. Maybe the toll booth??
But I DO know what the blood vessels aretheyre
the actual freeways, side streets, and back
alleys where all the action in your body occurs.
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10 Blood Vessels, contd.
Texas is about 800 miles up and down, and about
the same distance across.
But in that space, over 79,000 miles of highways
are laid out. That doesnt even count the
smaller roads.
Likewise, despite being around 5 or 6 feet tall,
your body has between 70 to 100 THOUSAND miles of
blood vessels. Thats worth 3 or 4 trips around
Earth.
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11 Blood Vessels, contd.
Blood vessels are lined with smooth muscles.
This gives them the ability to change thickness.
Some are more capable of this than others.
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12 Blood Vessels, contd.
Most of the red vessels you see is an Artery
carries blood away from the heart.
Most of the blue vessels here is a Vein carries
blood back to the heart.
Most diagrams like this show red as being high O2
blood. Arteries normally carry this to the rest
of the body.
Blue usually represents blood low in O2. Veins
take this blood back to the heart so that it can
be sent to the lungs to recharge.
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13 Blood Vessels, contd.
Think about what happens on big highways.
Traffic is moving so fast, that a postal worker
in her van wouldnt have a chance of driving by a
mailbox and getting anything in or out of it.
The arteries and veins are like thatway too
big, and way too much blood moving way too fast
for any cells to get the stuff they need out of
the blood.
Where does a postal worker do her work? On small
side streets, where traffic is very slow and very
orderly. Thats where trash pickup happens, too.
These so-important side roads and neighborhood
streets are the capillaries of your body.
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14 Blood Vessels, contd.
Capillary tiny vessel that connects arteries to
veins. Gases, nutrients, and wastes are
exchanged with cells in these.
You can think of the capillaries as places where
the blood exits one highway, conducts its
business, then makes a U-turn back to where it
started from down a different highway.
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15 STRUCTURE No.3Blood
What is blood, anyway? You might be surprised to
find out what its made of. It looks like a
smooth, red liquid, but looks can be
deceiving. Blood is actually made of different
cells tissues.
About half of the blood is plasma, the yellowish
clear liquid part of blood. Its mostly water.
LOTS of chemicals ride this liquid waterway in
the body.
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16 Blood, contd
Your body has trillions of red blood cells.
These disk-shaped cells are so packed together
that they make the blood appear red, instead of
showing up as little polka-dots in the
yellow fluid.
Red blood cells carry oxygen to the other body
cells, using a special iron compound to hold onto
the oxygen.
Red blood cells are made by the millions per day
in the middle of your bones!
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17 Blood, contd
White blood cells are solitary warriors.
Theyre way outnumbered by your RBCs, otherwise
your blood might be more pink than red.
WBCs fight germs and eat dead body cells. Useful
stuff, eh?
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18 Blood, contd
And when you get a cut, why dont you just bleed
and bleed and bleed to death? Thank your
platelets.
Platelets are blood cells that clump together
with special chemicals at a cut to make a clot.
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19 DISORDERS PROBLEMS
Its great when your circulatory system is
healthy runs flawlessly. But there are dozens
of problems that can arise when it becomes
worn down or dysfunctional due to disease
abuse. Wheres Joe?
Uhh ???
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20 Disorders, contd.
Lets say that Joe eats a bad diet. Lots of
greasy food, fried everything. On top of that, he
sits around all day and never really does
anything active. You can imagine
This isnt active? My thumbs hurt!
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21 Disorders, contd.
Joe is heading toward a condition known as
atherosclerosis. The combination of
high-cholesterol, fatty foods entering his blood
and little exercise, the fat clogs up the
insides of his arteries. Check it out
Barely any room for blood to get through, huh. On
top of the cramped space in there, the
cholesterol will damage scar the artery,
causing it to harden to where it doesnt bend
easily.
AVOID THIS CONDITION BY EATING LOW-FAT FOODS,
STAYING HYDRATED, AND EXERCISING.
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22 Disorders, contd.
What would be easier for your heart to pump a
teaspoon of water througha tiny little straw or
a nice, wide pipe?
But since Joe has been lazy and unhealthy, his
once-wide arteries are narrowed with blockage to
the size of straws. This condition,
called hypertension, is known as high blood
pressure. It basically means the heart works
way too hard to pump blood through vessels.
There are other causes of hypertension, but many
are avoidable. AVOID THIS CONDITION BY
EXERCISING, CHECKING YOURBLOOD PRESSURE, AND
AVOIDING EXCESSIVE SALT.
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23 Disorders, contd.
Joes feeling a little numb in his arm, yet his
fingers are tingling. A shooting pain rockets
past his elbow. Now his chest feels
tightreally tight.
Joe is likely experiencing the beginning stages
of a cardiac arrest. Better known as a heart
attack, it happens when one of the small arteries
feeding oxygen nutrients to the heart becomes
blockedthe heart muscle falls asleep and
could die. Joes life is in serious danger.
AVOID THIS CONDITION BY, WELL, ESTABLISHING
HEALTHY EATING EXERCISING HABITS NOW, WHILE YOU
ARE YOUNG.
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24 Will Joe Make It?
Lets spare Joes life this time.
Whew! Back to the X-Box!
And while some people never learn, hopefully you
have.
Lets review the Circulatory System real quick.
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26 Homeostasis/StimulusResponse

• Homeostasis how does the circulatory system
  help keep things in
• balance?
• Getting rid of wastes that would poison you
• Keeping the level of germs in your body at a
  manageable level
• Keeping cells far from your guts and lungs
  supplied with oxygen
• nutrients

Stimulus Response (something you respond to)
(how you respond) Harmful Virus enters the
body WBCs are produced to attack it Cut your
knee open bleed Platelets form scab to
prevent over-bleeding Tired muscles while
exercising much faster heart rate to feed
O2 NOW YOU THINK OF 2 MORE AND WRITE IN YOUR
NOTES!!
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25 Review
If your Circulatory System suddenly disappeared,
would you survive? To see, lets check the
functions of the circulatory system and see the
result of those things not happening any more.
1. Carries nutrients to cells from digested food
Joe would starve to death in a couple/few weeks
2. Carries oxygen to cells from inhaled air
Joe would suffocate to death in a few minutes
3. Carries wastes from cells to kidneys lungs.
Joe would poison himself to death in a few days,
probably
4. Fights diseases
This would be gruesome. You might be able to
literally watch Joe get eaten alive by bacteria
and other microbes in a matter of several hours.
YOU CANT LIVE WITHOUT IT!
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27 And Thats
THE
WAIT! One thinga lot of people ask about the
color of blood. Your blood is red, but the shade
of red depends on the oxygen content.
High-oxygen blood is a brighter red. Low-oxygen
blood, like in your veins, looks darker (almost
purplish). But its never blue. Blood is
just 2 shades of red. ?
END!