1. Circulatory System
Transport

2. Circulatory System
Transports nutrients, oxygen, and other substances to all cells in the body
These substances are transported in blood
Blood flows through a network of tubes called blood vessels
A pump, the heart, keeps blood flowing through the vessels

4. Circulatory System Humans have a double circulatory system
This means that blood needs to travel through the heart twice on one complete journey through the body

5. DOUBLE Circ. System
Blood on the left side of the heart came from the lungs
We call it oxygenated blood, because it has oxygen in it
Oxygenated blood is always colored RED

6. DOUBLE Circ. System
The oxygenated blood then goes around the body, delivering oxygen to body cells
This means the blood becomes deoxygenated
Deoxygenated blood is colored BLUE

7. DOUBLE Circ. System
When deoxygenated blood reaches the heart it gets pumped to the lungs.
Because the lungs are so close, blood is pumped at a _____ pressure (force)
When oxygenated blood reaches the heart it gets pumped to the rest of the body.
Because the body cells can be far away, blood is pumped at a _____ pressure (force)

8. Circulatory System review
What are 2 substances carried by the blood?
Blood travels through tubes known as what?
How many times does blood go through the heart in one complete circuit?
What kind of blood do we color red? Blue?
Why is there a pressure difference in blood going to the lungs, and going to the body?

9. Heart The function of the heart is to pump blood around the body.
The heart is made of a special type of muscle called cardiac muscle.
Your heart is about the same size as your fist.
It pumps over 5,000 quarts of blood every day

10. Heart The heart is divided into four chambers.
The two upper chambers are known as Atria (singular: atrium)
The two lower chambers are known as Ventricles
The left and right sides of the heart are completely separated by a septum.

12. Heart
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13. Heart
It is very important that oxygenated and deoxygenated blood DO NOT MIX.
This is achieved by having a septum that separates the left and right side of the heart
and…
By having valves that separate the atrium from the ventricle

14. Heart Valves Tricuspid Valve Bicuspid Valve
Separates the right atrium and ventricle
Has 3 parts or flaps
Bicuspid Valve
Separates the left atrium and ventricle
Has 2 parts or flaps

15. Heart Valves Semilunar Valves
Prevents blood from flowing back into the ventricles

16. How does the heart get the nutrients and oxygen it needs?
Blood does not spend enough time in the atria or ventricles to let oxygen and other nutrients fully diffuse to all the cells.

17. Coronary Arteries
On the outside of the heart are blood vessels that supply the cardiac muscle with oxygen and nutrients.
They are called
Coronary Arteries

18. Coronary Arteries
If a coronary artery gets blocked (by a blood clot, plaque, etc.) the cardiac muscles run short of oxygen.
If they don’t have oxygen they can’t respire.
This causes the heart to stop beating, otherwise known as a heart attack or cardiac arrest.

19. Coronary Heart Disease
Blockage of the coronary arteries is called Coronary Heart Disease.

20. Coronary Heart Disease
Very common cause of death (25%)
There are several factors that increase a person’s risk of getting this disease.
Diet
Smoking
Stress
Inactivity
Genes
And many others