1. 14-1 THE BODY’S TRANSPORT SYSTEM
Ch. 14, Section 1

2. THE CARDIOVASCULAR SYSTEM
Also called the circulatory system.
Consists of the heart, blood vessels, and blood.

3. THE CARDIOVASCULAR SYSTEM
Carries needed substances to cells.
Carries waste products away from cells.
Blood contains cells that fight disease.

4. DELIVERS NEEDED SUBSTANCES
Most substances that need to get from one part of the body are carried by blood.
Oxygen, glucose, other nutrients.

5. REMOVING WASTE PRODUCTS
Picks up waste from cells.
Carries carbon dioxide to the lungs where it is exhaled.

6. FIGHTS DISEASE
Transports cells that attack disease-causing microorganisms.
Keeps you from getting sick and helps you get well.

7. THE HEART
Heart: a hollow, muscular organ that pumps blood throughout the body.
Each time the heart beats, it pushes blood through the blood vessels of the cardiovascular system.
About the size of your fist.
Doesn’t get tired.

8. THE HEART’S STRUCTURE
The right side of the heart is completely separated from the left side by a wall of tissue called the septum.
Each side has two compartments, or chambers – upper chamber and lower chamber.

9. ATRIA
Atrium – Upper chamber that receives blood that comes into the heart.
There’s one atrium on each side.

10. VENTRICLES
Ventricle – lower chamber that pumps blood out of the heart.
There’s one ventricle on each side.

11. VALVES The atria and the ventricles are separated by valves.
A valve is a flap of tissue that prevents blood from flowing backward.
Valves are also located between the ventricles and the blood vessels.

12. HOW THE HEART WORKS Two main phases:
The heart muscle relaxes and the heart fills with blood.
The heart muscle contracts and pumps blood forward.
A heartbeat can be heard during the pumping phase.

13. HOW THE HEART WORKS
Blood flows through the valves from the atrium to the ventricle.
When the ventricles contract, the valves close so the blood doesn’t go back into the atrium.

14. BLOOD VESSELS Arteries: Capillaries: Veins:
are blood vessels that carry blood away from the heart.
Blood flows from the arteries to the capillaries.
Capillaries:
Substances are exchanged between the blood and body cells.
Blood flows from the capillaries to the veins.
Veins:
Blood vessels that carry blood back to the heart.

15. PATTERN OF BLOOD FLOW
In the first loop, blood travels from the heart to the lungs and then back to the heart.
In the second loop, blood is pumped from the heart throughout the body and then returns again to the heart.
Heart is really two pumps – right to the lungs, left to the rest of the body.
Blood travels in only one direction.

16. RIGHT ATRIUM Upper chamber on right side.
Receives blood from the body.
Blood is low in oxygen and high in carbon dioxide.
Blood flows in when the heart muscle relaxes.
When the atrium contracts, blood squeezes blood through the valves into the ventricles.

17. RIGHT VENTRICLE Lower chamber on the right side.
Pumps oxygen-poor blood to the lungs.
When the ventricle contracts, blood gets pushed toward the lungs.

18. LEFT ATRIUM Upper chamber on the left side.
Oxygen-rich blood comes in from the lungs.
When the atrium contracts, blood squeezes blood through the valves into the ventricles.

19. LEFT VENTRICLE Lower chamber on the left side.
Pumps oxygen-rich blood to all parts of the body.
When the ventricle contracts, blood gets pushed into the aorta which carries blood to the body.

20. ARTERIES When blood leaves the heart, it travels through arteries.
Artery structure: Walls are generally very thick – three cell layers.
Pulse: the repeated rise and fall of the arteries that you can feel.
Regulating blood flow: the layer of muscle in an artery acts as a control gate, adjusting the amount of blood sent to different organs.

21. CAPILLARIES
In the capillaries, materials are exchanged between the blood and the body’s cells.
Capillary walls are only one cell thick.

22. VEINS
Blood moves from the capillaries into the veins, which carry blood back to the heart.
He walls of veins have three layers.

23. BLOOD PRESSURE
Water can flow through a hose with different amounts of pressure.
Low pressure
High pressure

24. BLOOD PRESSURE What causes blood pressure?
The force with which the ventricles contract causes the blood pressure.

25. BLOOD PRESSURE Measuring Blood Pressure
Using a sphygmomanometer – a cuff around the arm.
Measures the pressure when the blood vessels contract and when they relax.

27. Organ Systems