Here Is Your Heart

Let’s Find Out!

How Does It Work?

Amazing Facts!

• The heart beats an average of 3 billion times during your life.

• About 8 million blood cells die every second.

• It takes 20 sec. for a red blood cell to circulate the whole body.

• The heart pumps about 1 million barrels of blood during the average lifetime.

The Heart• The Heart Is A Muscle

• Divided Into Left And Right Halves

• It Pumps The Blood

• 5 Liters Per Minute When You Are At Rest

Where Does The Blood Go?

• To The Head

• To The Limbs

• To The Internal Organs

• To The Skin

• To The Heart Itself

• Everywhere!

Through Arteries

• Carry Blood Away From The Heart

• Muscular Walls

• Maintain Blood Pressure

• Oxygen Rich Blood

To The Capillaries• One Cell –Layer

Thickness• Site Of Gas

Exchange• Cells Pass Single

File• Help Control Body

Temperature

To The Veins

• Carry Blood Back To The Heart

• Less Muscular

• Low Pressure

• Oxygen-Poor Blood

• Contain Valves

And Back To The Heart

During Your Lifetime

• Your Heart Will Beat Some 2.5 Billion Times

• Pump Enough Blood To Fill About 2000 Swimming Pools

• And Never Stops To Rest

How Does It Do It?

The Heart Has 4 Chambers

Right Atrium

Left Ventricle

Left Atrium

Right Ventricle

Let’s Follow The Flow

1. Body To Right Atrium

2. To Rt. Ventricle

3. To The Lungs

4. From The Lungs To The Lt. Atrium

5. To Lt. Ventricle

6. Out To The Body

The Right Side…

• Oxygen-Poor Blood Enters The Heart At The Right Atrium

• Passes Through The Tricuspid Valve

• Enters The Right Ventricle

• Passes Out Through The Pulmonary Artery

RA

RV

PA

To The Lungs Where…

1. Waste Carbon Dioxide Is Removed

2. Needed Oxygen Is Gained

3. Exits Through The Pulmonary Veins To…

…The Left Side• Oxygen-Rich Blood

Enters The Left Atrium• Passes Through The

Bicuspid (Mitral)Valve• To The Left Ventricle• Out The Aorta To The

Body

LA

LV

Let’s Watch It Happen

Very Cool!

The Heart Is Controlled By Electrical Signals

Pacemakers

• Coordinate Contraction

• SA Node Initiates

• AV Node Continues

• Conduction Pathways Finish

Artificial Pacemakers

Control Pace When The Heart Can’t

Coronary Circulation• Begins In Aorta• Supplies The Heart

Muscle With Blood• Shown Here In An

Arteriogram• Narrowing Can Cause

Pain (Angina)• Blockage Results In A

Heart Attack (M.I.)

Narrowing Can Occur In Other Arteries Too

We Can Check The Heart With An Echocardiogram

• Sound Is Used

• Shows The Chambers

• Shows The Valves

• Shows Blood Flow In Color

• It’s Painless

To Be Heart HealthyExercise Regularly

Eat Heart-Healthy Meals

Reduce Stress

Don’t Smoke

Get Plenty Of Rest

OTHER ANIMALS MAY CIRCULATE BLOOD

DIFFERENTLY THAN IN MAMMALS

PART - 2

Do Worms Have Hearts?

• Worms have a closed circulatory system. Their blood travels through vessels.

• Worms have 5 “heart arches” that move blood through vessels.

• The top vessel carries blood forward.

• The bottom vessel moves blood rearward.

• Worms don’t have red blood cells.

WORM CIRCULATION

INSECT CIRCULATION

• Insects have an open circulatory system.

• Blood doesn’t flow through vessels

• Blood doesn’t carry oxygen and isn’t red.

• Insects don’t need much oxygen.

Other Heart Arrangements