1. The Cardiovascular System
Ms. Marcos

2. Questions you can answer after learning about the Cardiovascular System:
Why could you faint if you stand at attention for a long time?
Why can you feel nauseous if you are in a sudden stressful situation?
What makes the Boom-boom sound of a heart beat?
How is the heart disconnected during open heart surgery?
Why does your heart rate increase with exercise?
What is a “pacemaker” and what does it do?
What is hypertension? What is hypotension?

3. Big Questions about the Cardiovascular System:
Why do we need a cardiovascular system?
What does blood do?
How does blood move around the body?
Answer these questions on your own, then share your answers with a partner.
Watch Tim and Moby explain about the cardiovascular system and add more information to your answer!

4. Label the blood vessels!
Vein
Pulmonary vein
Label the blood vessels!
Lung (pulmonary) capillaries
Body capillaries
Pulmonary artery
Artery

5. What types of blood vessels are there?
Arteries:
Carry blood AWAY from the heart
A few, strong vessels
Veins:
Carry blood TO the heart
More, weak vessels
Capillaries:
Exchange gases and nutrients in the blood with tissues
Many, very small vessels

6. Now try to label this one!
Body capillaries
Vein
Now try to label this one!
Pulmonary artery
Pulmonary artery
Lung capillaries
Artery
Lung capillaries
Pulmonary vein
Pulmonary vein
Left Atrium
Right Atrium
Left Ventricle
Right Ventricle
Artery
Vein
Body capillaries

7. See the diagram on the next slide!
A closer look…
What are arterioles?
Small arteries (one artery leads to more arterioles)
What are venules?
Small veins (small venules lead to one vein)
How large and flexible are:
Arteries and arterioles?
Veins and venules?
Capillaries?
See the diagram on the next slide!

8. Blood vessels arteries arterioles capillaries venules veins veins
artery
arterioles
venules
arterioles
capillaries
venules
veins

9. Artery Vein Capillaries
Thin walls
Allow diffusion
Valve
(prevents backflow)
Thick muscle (holds high pressure blood)
Thin muscle (only low pressure blood inside)
Artery
Vein
Capillaries

10. Explain the differences
Which one carries blood away from the heart?
Which one has thicker muscle?
Why does it need to be thicker?
Which one carries blood to the heart?
Which one has a valve?
Why does it need a valve?

11. Why are capillaries so small?
They need to DIFFUSE things
IN and OUT
GOOD stuff going OUT to body tissues:
Nutrients, O2
BAD stuff going IN from body tissues:
Wastes, CO2

12. Are they always filled with blood?

13. Are they always filled with blood?
Small muscles stop blood flow
Only the parts that NEED blood right away have it
(Many body parts take turns getting blood)
Why would you want to cut off blood flow to capillaries in a certain area?
Hint: Injury!

14. Changing blood flow… an example
Send blood to the brain and muscles
Send blood away from the digestive system
If you are being chased by a BEAR…
You need to get away FAST!
Result:
You might feel nauseous because of less blood going to your stomach

15. How does blood get back to the heart after going through the capillaries?
Blood returns to the heart
Valve lets blood flow only in one direction
Muscle pushes on the vein

16. How veins work… an example
When guards stand still for a long time, the blood moves down to their feet and can’t get back up. It can cause them to faint.
Raise one hand and keep the other hand down.
Activity:
Wait 1 minute.
Now look at your palms!
Explain this using what you know about veins and valves!
Were your hands different colors?
Why?

17. The Heart: A few definitions
Latin roots:
Myo = Muscle
Cardium = Heart
Peri = Around
Myocardium
Heart muscle
Pericardium
Tissue surrounding the heart
Pericardial sac
Tissue sac with liquid around the heart

18. Label the parts of the heart!
Pulmonary artery
Aorta
Label the parts of the heart!
Pulmonary artery
Vena cava
Left Atrium
Right Atrium
Pulmonary veins
Pulmonary veins
Semilunar valve
Semilunar valve
AV valve
AV valve
Vena cava
Right ventricle
Left ventricle

19. What makes the sound of your heart beat?
Watch it happen!
Check out these animations:
The heart parts QUIZ
The heart from the outside
The heart both inside and outside
The valves
The valves from the inside
What makes the sound of your heart beat?

20. What would happen if…
You had a hole in your septum (the dividing muscle between the right and left ventricles)?
You had a hole between your atria?
You had a connection between your aorta and your pulmonary arteries?
Septum

21. How do you control heart contraction?
Systole is…
When the heart muscle contracts
Diastole is…
When the heart muscle relaxes
Nodal tissue
Is very special… it has both nerve and muscle tissue

22. SA node (sino-artrial node)
Gets the signal from the brain and makes the atria contract
Sends the signal to the AV node
AV node (atrio-ventricular node)
Makes the ventricles contract all together
Pacemaker
(SA node) 1 2 3 4
Right atrium
Right ventricle
AV node
Specialized muscle fibers
ECG

23. What does blood pressure mean?
What is your pulse?
Does it measure blood flow in arteries or veins?
Your pulse is a wave of blood moving through your arteries
What is blood pressure?
Which vessels have the highest pressure?
Arteries have the highest pressure, then capillaries, then veins
Muscles need to push the blood back to the heart through your veins

25. How do you measure blood pressure?
Watch the Blood Pressure Animation!

26. What is normal blood pressure?
Usually around 120 / 80 mmHg
Why is blood pressure written as two numbers?
The first number means…
When the ventricles contract and push blood through arteries
The second number means…
When the ventricles relax and the blood keeps moving through (at lower pressure)
Which is systolic and which is diastolic pressure?
Systolic
Diastolic

27. Blood pressure problems
Hypotension is
when blood pressure is too low
Hypertension is
when blood pressure is too high

28. Put the following terms in order:
Right Atrium
Left Atrium
Pulmonary Veins
Venules
Arteries
Veins
Arterioles
Right Ventricle
Body Capillaries
Superior/Inferior
Vena Cava
Lung Capillaries
Pulmonary Arteries
Aorta
Semilunar valve
Left Ventricle
AV valve

29. Check your answers with these animations:
How the blood circulates
Music Video