Circulatory System

• Transports nutrients and oxygen to the body cells

• Transports waste products (carbon dioxide, excess water, salts) away from the body cells

• Heart lungs heart cells

Structures of the Circulatory System

• Heart– Composed of cardiac muscle– Has 4 chambers to separate oxygen rich from

oxygen poor blood

• Arteries

• Veins

• Capillaries

Mitril Valve

Aortic Valve

Tricuspid Valve

Pulmonary Valve

Right Atrium

Left Atrium

Right Ventricle

Left Ventricle

Aorta (blood to body)

Superior Vena Cava(blood from body)

Pulmonary Artery(blood to lungs)

Pulmonary Veins(Blood from lungs)

Septum

Arteries

• Blood vessels which carry blood away from the heart

• Most arteries carry oxygen-rich blood

• Arteries are round with thick walls of smooth muscle

• Arteries are found deep within

the body

• Most are under high pressure

Veins

• Blood vessels which carry blood to the heart• Most veins carry oxygen-poor blood• Veins are oval shaped with thin muscular walls• Veins have valves to present the backward flow

of blood• Veins are located near the

surface of the body• Veins have a low pressure

Capillaries

• The tiniest of blood vessels which join arteries and veins

• Site of gas exchange (oxygen is given to the body cells and carbon dioxide is put into the bloodstream)

• Site where nutrients are given to the body cells and waste products (salts, excess water) are put into the blood stream

• Microscopic and thin walled

Blood

• Red Blood Cells– Small and disc shaped with no nucleus– Carries oxygen in the bloodstream, on hemoglobin– Make all new red blood cells every 14 days

• White Blood Cells– Small, amoeba-like in shape and movement– Fight infection and disease– Filter dead red blood cells from the blood stream– Has nucleus

More Blood

• Platelets– Tiny and colorless, look like torn pieces of

red blood cells– Proteins used to help repair injured blood vessels (“clot” blood)

• Plasma– Yellow colored fluid which makes up the majority of

blood– Composed of water, glucose, vitamins and minerals– Provides a medium through which blood cells can

move