Blood Flow and Blood Vessels in the Cardiovascular System

Nicole Bajier, Bryan Berg, Daniel Kim

Major Veins and Arteries Around the HeartSuperior vena cavaInferior vena cavaAortaPulmonary arteries (right pulmonary

arteries and left pulmonary arteries) Pulmonary veins (right pulmonary

veins and left pulmonary veins)Arteries carry blood away from heart.Veins carry blood towards the heart.

Flow of Blood Through Heart

Structure of Blood VesselsWalls of arteries and veins are in 3

main sections:- tunica interna or tunica intima: innermost layer of a blood vessel- tunica media: middle layer, it contains smooth muscle tissue in a framework of collagen and elastic fibers.- tunica externa or tunica adventita: forms a sheath of connective tissue around the vessel.

ArteriesArteries are in charge of transporting blood

away from the heart.Elastic artery: large and extremely resilient

vessels with diameters up to 2.5 cm. (examples: pulmonary trunk and aorta)

Muscular artery: also known as medium-sized arteries or distribution arteries. They distribute blood to skeletal muscles and internal organs. (example: external carotid artery of the neck)

Arteriole: small arterial branch that delivers blood to a capillary network. It is the smallest of arteries.

Capillaries

Capillary bed: an interweaving network of capillaries supplying to an organ.

Precapillary sphincter: a band of smooth muscles guarding the entrance of each capillary .

Main Function: the exchange of molecules between blood and interstitial fluid.

VeinsVeins are in charge of transporting blood

from various parts of the body to the heart.There are three main types of veins:Venules: the smallest type of vein that

resemble expanded capillaries.Medium-sized veins: comparable in size to

the muscular arteries.Large veins: largest of the veins, it includes

two venae cavae and their tributaries in the abdominopelvic and thoracic cavities.

Works CitedEssentials of anatomy &

Physiology 4th editionhttp://

farm3.staticflickr.com/2412/2275511879_b2132d25a5.jpg

http://upload.wikimedia.org/wikipedia/commons/a/ae/Circulation_of_Blood_Through_the_Heart.jpg

http://www.rci.rutgers.edu/~uzwiak/AnatPhys/Blood_Vessels_files/image004.jpg