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The Circulatory and Respiratory Systems

How are the two systems controlled?

Autonomic nervous system

What is the FUNCTION of the circulatory system?

• To bring oxygen to tissues/organs throughout the body

• To remove carbon dioxide from tissues/organs throughout the body

How does this happen?

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The Circulatory System

• Organisms with a few cells can obtain and remove nutrients and wastes by diffusion. These organisms do not have a circulatory system.

• Vertebrates, like man have a CLOSED circulatory system.

• The human circulatory system consists ofthe following three components:

the heart, the blood vessels, the blood

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Heart Structure

Heart is made up mostly of:Muscle, known as the MYOCARDIUM_________________________

It is surrounded by a protective sac known as the : PERICARDIUM________________

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Heart Structure

The heart has 4 chambers.

_______________________________

The top 2 chambers are called:right atrium, left atrium or atria

The bottom 2 chambers are called:

right ventricle, left ventricle___________________________

Receive blood into heart

Pump blood out of heart

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The Heart Beat

The heart has 4 main valves to control blood flow through the heart.

Valves prevent backflow of blood.

Circulation is a closed circuit. It is ONE-WAY.

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Setting the Heart PacemakerSinoatrial Node and Atrioventricular Node

Node = group of neurons sending electrical signals

STEP 1: Bloodatria to ventricles

STEP 2: Blood out of heart

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The Heart Beat

Systole - Heart is pumping blood, contracting muscle• atria to the ventricles• ventricles to body or lungs

Diastole – Heart is relaxing• atria fill with blood

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The LUB: Closing off the atria Involves the TRICUSPID and MITRAL valves

The DUB: Closing off the ventriclesInvolves the PULMONARY and AORTIC valves

What Makes that LUB-DUB Sound?

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Video of heart structure and function