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SUMMARY, OBJECTIVES, AND STANDARDS

Review module

04.01 Cardiovascular System
Review major functions of the cardiovascular system and the role of the heart in maintaining circulation of blood throughout your body, some of the factors that affect cardiovascular health

Review assessment

04.01 assignment submission

By the end of this class you will

Know the structure of the heart, how it pumps blood
Understand blood pressure and be able to describe factors affecting it
Complete the worksheets from pages 2, 3, and 5
Successfully complete assessment submission for 04.01

STANDARDS�HE.912.C.1.7: Analyze how heredity and family history can impact personal health.�SC.912.L.14.36: Describe the factors affecting blood flow through the cardiovascular system. �SC.912.L.14.39: Describe hypertension and some of the factors that produce it.

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THE CARDIOVASCULAR SYSTEM

Transports needed oxygen and nutrients to all the cells of your body.
HOW? By pumping blood through blood vessels that extend to all your muscles, organs, and body tissues.
According to the Oxford Handbook of Clinical Medicine, it pumps at least 2,000 gallons of blood a day and will beat over three billion times during a person's lifetime

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HOW DOES BLOOD FLOW?

There are a total of four chambers in the heart, two on each side.
The upper chambers are called atria and the lower chambers are called ventricles.
The pumping action of the heart has two main periods: a period of relaxation called diastole the period of contraction called systole.
In diastole, the period of relaxation, blood enters from the atria into the ventricles through valves called AV valves.
In the period of contraction, systole, the ventricles contract.
Oxygen-depleted blood flows out of the right ventricle into the pulmonary artery.
The pulmonary artery has two branches, each of which goes to a lung. Here, blood picks up oxygen and gives off carbon dioxide.
From the left ventricle, oxygen-rich blood enters the largest artery in the body, the aorta.
Arteries stemming off the aorta carry oxygen-rich blood to all parts of the body.
When the atria relax, oxygen rich blood from the lungs enters the left atrium, and oxygen poor blood from the rest of the body enters the right atrium, starting the process all over again.

Click the heart for a video

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HOW DOES BLOOD FLOW?

It’s the valves opening and closing that makes the sound you hear.
The two bottom chambers (ventricles) of your heart fill when the heart muscle relaxes.
The heart muscle contracts and pushes the blood from the bottom ventricles to the lungs and body.
The valves between the top two chambers (atria) and the bottom chambers (ventricles) close so the blood moves in one direction. That’s what makes the first sound of your heart beat.
A second set of valves open to the let the blood flow out of the bottom chambers (ventricles) and to the lungs and body. When they close again, it makes the second beat of your heart.
One type of heart murmur occurs when one of the heart valves can’t open or close completely.

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BLOOD FLOW IN THE HEART

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BLOOD PRESSURE

Determined by

The strength of your heart muscle as it pumps blood through the body
Kidneys, which control blood volume

Remove excess water from your bloodstream in order to decrease the total amount of blood in your body.
The more blood there is in your bloodstream, the more pressure there is on the walls of your blood vessels.

The nervous and endocrine systems impact blood pressure

The smooth muscles of your blood vessels can constrict, decreasing the size of the opening available for blood flow.

Increases blood pressure as the blood surges through your body

And vice versa

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BLOOD PRESSURE

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BLOOD PRESSURE

Factors that affect blood pressure

Genetics
Lifestyle

Atherosclerosis: a narrowing of the arteries due to an accumulation of fatty deposits called "plaque" on the inner walls of arteries.

Plaque not only impedes blood flow, contributing to high blood pressure, but it can also promote clotting, which can stop the flow of blood.
Occurs in coronary arteries, those that supply blood to the heart, become partially or completely clogged with plaque can lead to a heart attack or heart damage
Clot obstructs blood flow to the brain, a stroke occurs.
Both heart attacks and strokes can cause death or severe disability.

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BLOOD PRESSURE

DO:

Exercise vigorously five to six times per week for at least 45 to 60 minutes.
Eat a well-balanced diet low in salt and low in saturated fats.

Saturated fats are found in foods made from animal products such as milk, cheese, and red meats.
Contain specific types of fats containing cholesterol, which is known to form plaque on the walls of arteries in some people.