The transport system of the body
Cardiovascular System OR The Circulatory System
The Circulatory Systemconsists of
*the heart,
*the blood vessels,
and
*around 5 litres of blood
Function: transports oxygen, nutrients, hormones, and cellular waste products throughout the body.
The Heart
The Heart
The Hearta muscular pumping organ located between the lungs
behind the sternum. It is the body’s hardest-
working organ and only about the size of a closed fist.
Two pumps in one small package
RIGHT side pumps blood to the lungs
LEFT side pumps blood to the body
Valves in the heartAct to prevent blood from flowing backwardsSlam shut every time the heart contracts to build pressure and drive blood forwardshttp://youtu.be/JA0Wb3gc4mE
CHORDAE “The heart strings” Tether the valve to the heart wall
like parachute strings Hold the valve in place
Heart Strings
Blood Vessels are the body’s
highways that allow blood to flow quickly
and efficiently from the heart to every region of the body
and back again.
Arteries *blood vessels carrying blood away from the heart to tissues*thick muscular walls *hold blood under very high pressure
Capillaries *the smallest branches of the circulatory system*have thin leaky walls to allow materials to pass out and into the blood
Capillary facts:>10 billion capillariesbarely the diameter of a single red blood cell If all the capillaries in your body were placed end to end, they would circle the globe
Fibrous Connective Tissue shows that every cell is not far from a capillaryhttp://bcrc.bio.umass.edu/histology/?q=node/233&size=_original
Capillaries in Lung tissue
Blood vessels preserved in the hand
Preserved vascular system
Hand
Veins *carry blood back to the heart*have thin walls compared to arteries, because blood pressure is low*They have valves to prevent back flow.
Relative size of arteries, veins and capillaries
Blood A type of connective tissue Made up of a base fluid called
plasma Erythrocytes (RBC) Leukocytes (WBC) Platelets Dissolved chemicals such as
glucose, fatty acids, proteins, amino acids, hormones,