CHAPTER 46The Cardiovascular System

We are talking about your heart• Everyday your heart creates enough energy to drive a

truck 20 miles• Your heart beats 100,000x a day• Owning a cat can reduce heart attacks by 1/3• Your heartbeat changes and mimics the

• music you listen to

• Vegetarians are 19% less likely to die from heart disease, a study found.

• Smoking makes the risk of a heart attack 200% to 400% greater than that of nonsmokers.

Lets look at your heart• External Internal

Blood VolumeYour body has about 5 liters of bloodMen have more than women

What are the parts of your heart?• Atrium- Upper chambers of

the heart

• Ventricles-Lower chambers of the heart

• Valves- flaps of tissue that open in only one direction

How does your blood flow?

Blood flow• Deoxygenated blood enters the right atrium• Right atrium sends deoxygenated blood into the right ventricle• Right ventricle contracts and forces blood into pulmonary

arteries• Pulmonary artery sends blood to the lungs

• Here the carbon dioxide diffuses out of the blood and oxygen diffuses into the blood

• The oxygenated blood returns to the left atrium of the heart• The oxygenated blood is then pumped into the left ventricle• Contraction of the muscular walls of the left ventricle forces

blood into a large vessel called the aorta

You have two types of circulation• Pulmonary circulation-is the portion of the

cardiovascular system which carries deoxygenated blood away from the heart, to the lungs, and returns oxygenated (oxygen-rich) blood back to the heart.

You have two types of circulation• Systemic circulation-is

the part of the cardiovascular system which carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart.

Your Pulse• Do you know how to take

it?• Try it out• Find the artery in either your

arm or leg.• Count the beats for 10

seconds and multiply by 6

• Your resting heart rate can determine your health

Your health and your heart• How can we make a happy heart?

• Avoid smoking and using tobacco products.• Be physically active every day.• Eat a heart-healthy diet.• Keep a healthy weight.• Keep your blood pressure healthy.• Keep your total cholesterol healthy.

How can you make your heart sad?• Just do all of the opposite from the page before!• Don’t be healthy• Drink• Smoke• Drugs• Diet full of cholesterol, fat, sugars

Effects of a poor diet on your heart• Atherosclerosis- the hardening and narrowing of the

arteries

This is the result of too much cholesterol in your diet

More effects• Hypertension- also known as high blood pressure

• This is a condition when the pressure on the walls of the artery are too great

• Your blood pressure measures your systolic and diastolic pressures• Systolic-left ventricle is most contracted• Diastolic-when the left ventricle is most relaxed before contraction

• Have you ever heard of numbers like 120/80?• Systolic is the top number and is usually between 100-140• Diastolic is the bottom and is between 60-90

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