Circulatory System Circulatory System Includes Blood heart and

Circulatory System

Circulatory System • Includes: – Blood, heart and blood vessels • Purpose: – Delivers oxygen and nutrients to all parts of the body – Carries wastes (ex. Carbon dioxide) from tissues for disposal

Did you know? • No body cell is farther than two cells away from a blood vessel that can carry nutrients!

Blood • Red blood cells – 50% of blood – Contain a protein called hemoglobin, which allows RBCs to transport oxygen • White blood cells – 1% of blood – Infection-fighting cells

Blood • Platelets – 1% of blood – Tiny cells that help with blood clotting • Plasma – Almost 50% of blood – Protein rich liquid that carries blood cells

Did you know? • During an average lifetime, the heart pumps enough blood to fill two large ocean tankers!

• Arteries Blood Vessels – Carry blood AWAY from the heart (usually oxygenated) – Walls are thicker to withstand the greater pressure • Veins – Carry blood TOWARD the heart (usually deoxygenated) – Walls are thinner because of lower pressure – One way valves • Capillaries – Tiny, thin-walled blood vessels that allow the exchange of gases, nutrients and waste – Some only fit one cell through at a time

Arteries to Veins Arteries Arterioles Oxygenated blood Capillaries Venule Vein Deoxygenated blood

Artery vs Vein

Artery vs Vein

Capillaries

Did you know? • There are 96 000 km of blood vessels in your body to sustain your 100 trillion cells!

Heart • Structure: – 2 atriums • Receive blood from body and pump to ventricles • Thin walled – 2 ventricles • Pump blood to body tissues • Thick, muscular walls – Right side pumps deoxygenated blood to the lungs to get oxygenated – Left side pumps oxygenated blood to the body

Right side Left side

Did you know? • The only artery in the body that pumps deoxygenated blood is the pulmonary artery. • The pulmonary artery pumps blood from the heart to the lungs to be oxygenated!

Heart Anatomy

• Video: Circulatory System

Important Blood Vessels to know • Arteries: – Pulmonary Artery – Aorta • Veins: – Superior vena cava – Inferior vena cava – Pulmonary vein