The Heart and Circulation

What is the circulatory system’s job?

Carries needed substances to cells

Carries waste products away from cells

Function of the Circulatory System

Needed SubstancesMost substances

that need to get from one body part to another are carried by the blood.

OxygenGlucose (sugar)

Waste ProductsWhen a cell uses

glucose, it produces carbon dioxide as waste.

The cardiovascular system carries it to the lungs.

Then it is exhaled.

Disease FightersThe

cardiovascular system also carries cells that fight disease.

White Blood Cells

HeartLungsArteriesVeinsCapillaries

There are Five Main Parts to the Cardiovascular System

• What are the main parts of the cardiovascular system?

The HeartA hollow muscle that

pumps blood.Made of cardiac

muscle. It does not get tired.

It rests only between each beat.

Every minute, the heart can pump 5 Liters of blood.

Hand out Heart Parts sheet.

Heart Parts

Backwards heartHuman heart has 4 chambersTwo upper chambers are called atria (plural)

or atrium (singular)

The Heart Model

Deoxygenated Blood

Blood that has very little oxygen in it.

This blood has been pumped out to the body and given the oxygen to the cells.

BLUE

This blood has just come from the lungs, where it picked up oxygen.

It is pumped out to the body, full of oxygen.

RED

Blood

Oxygenated Blood

AlveoliSmall sacs

where gas exchange takes place.

Each alveoli is wrapped in capillaries.

Right AtriumRight Atrium

receives deoxygenated blood.

It is low in oxygen and high in carbon dioxide.

Superior Vena CavaBrings oxygen low

blood from the upper body to the heart.

From the headFrom the arms

Brings oxygen low blood from the lower parts of the body to the heart.

LegsInternal organs

Right Atrium Receives Blood

Inferior Vena Cava

Left AtriumReceives blood from

the lungs. It is high in oxygen

and ready to be pumped out to the body.

Left Atrium Receives BloodReceives oxygen rich

blood from the lungs through the:

Anyone know another word for the lungs?

PulmonaryVein

Right VentricleReceives blood from

the right atrium.Pumps oxygen poor

blood to the lungs.

Left VentricleReceives blood from

the left atrium.Pumps oxygen rich

blood to all parts of the body.

SeptumThick, muscular wall

that separates the two sides of the heart.

Prevents oxygen rich blood from mixing with oxygen poor blood.

Blood Leaves the Heart to go to the Lungs

The oxygen low blood leaves the heart to go to the lungs to pick up oxygen.

Leaves the heart through the:

PulmonaryArtery

Blood is Pumped Out to the BodyLeaves the heart

through one artery.Largest artery in the

body.Aorta

ValvesValves allow blood to

move through, but do not allow it to move backwards.

The heart has four valves.

The valve that allows blood into the aorta.

Aortic Valve

Valve that allows blood into the Pulmonary Artery.

Pulmonary Valve

Valve that allows blood to travel from the right atrium to the right ventricle.

Tricuspid Valve

Valve that allows blood to travel from the left atrium to the left ventricle.

Mitral Valve