CIRCULATORY
SYSTEM
TABLE OF CONTENTS
01
DEFINITION AND
PURPOSE
03
HOW IT WORKS
02
COMPONENTS
04
COMMON
MISCONCEPTIONS
CIRCULATORY SYSTEM
A body system responsible for carrying
blood, nutrients, and waste throughout the
body
02
COMPONENTS
THREE MAIN PARTS
1. HEART
2. BLOOD VESSELS
3. BLOOD
1. HEART
Made out of an special muscle
Every heartbeat is when it contracts and
relaxes to pump blood
• 4 chambers :
+ 2 upper chambers are called atriums
+ 2 lower chambers are called ventricles
+ The atria receives blood
& the ventricles pumps out blood.
• Pulmonary artery & vein are the ones on
charge of pumping blood to and from the
lungs
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2. Blood vessels
Artery
• Veins
Cappilaries
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ARTERY
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Has thick elastic walls , small lumen
Carries blood away from heart (usually
oxygenated blood) -> other organs
Has a pulse when streches
It can withstand high pressure
Main artery is the aorta
Veins
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Has thin walls, large lumen and vavle
Vavles prevent backflow
Carries blood back to the heart
(usually low oxygenated blood)
No pulse
Can’t withstand high pressure
Cappilaries
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Has a single cell wall
Has gaps to allow subtances to
enter/leave
Small
Forms in huge networks
Exchanges oxygen and carbon dioxide
3. Blood
Blood components
Plasma (55%)
• Red blood cells (44%)
• White blood cells (0.7%)
• Platelets (0.3%)
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Types of blood
1. Oxygenated blood
• Oxygen concentration is high
• Carbon dioxide concentration is low
• Bright red in color
• Flows away from the heart
• Main fuction : supply oxygen to our body
2. Deoxygenated blood
• Oxygen concentration is low
• Carbon dioxide concentration is high
• Flows towards the heart
• Main function : carry CO2 to the lungs
3. How it works
4. Common misconceptions
- Arteries only carry oxygenated blood
and veins only carry deoxygenated
blood.
This is true most of the time.
However, the pulmonary arteries and
veins are an exception to this rule.
Pulmonary veins carry oxygenated
blood towards the heart and the
pulmonary arteries carry
deoxygenated blood away from the
heart.
4. Common misconceptions
Blood is could be in other colors besides red.
Veins can appear blue/green as we see them
through our skin, leading some people to
believe that blood there is blue. However, this
is not the case! Blood only appears blue
because of the way skin absorbs light.
Although oxygen does have an effect on the
brightness of the blood (more oxygen makes a
brighter red, less makes it darker).
Thank you
for listening