Blood Vessels: Cardiovascular System

STRUCTURE AND FUNCTION ONLY

Explain why the human cardiovascular system is a closed system of tubes

it carries the blood away from the heart, transport it to tissues, and returns it to the heart, they never exit freely into the body cavities

Lumen of a blood vessel

the space within an artery, vein, intestine, renal tubule or any tubular structure, there for blood flow and pressure with blood

Arteries Function

carry blood away from the heart to other organs

Veins function

are the blood vessels that convey blood from the tissues back to the heart

What is the role of capillaries 

allow exchange of gas and nutrients

allow oxygen to diffuse from the blood into surrounding tissues

transport nutrients (glucose etc) from blood to the cells 

Tunics (they are part of the wall of the arteries and veins)

tunica intima (inner lining), tunica media (middle layer of smooth muscle and elastic CT) and tunica externa ( CT outer covering)

Tunica Interna’s endothelium is

simple squamous epithelial cells, its for blood to flow smoothly

How does the endothelium of tunica internal prevent thrombus (blood clot)

they release anticlotting chemical factors 

Vasa Vasorum (such as the aorta)

in tunica externa, they are blood vessels that supply nutrients to large arteries or veins

Anastomoses and the alternate routes for blood flow

is an end to end of joining blood vessels, lymphatic vessels or nerves

provides arteries for alternate routes

may occur between veins and between arterioles and venules

Collateral circulation

is the alternative route of blood flow to a body part through an anastomosis 

Elastic (conducting) arteries structure and function

largest arteries, elastic membrane in tunica intima , thick tunica media, thin tunica externa, and they conduct blood from the heart to muscular arteries

Muscular Arteries structure and function

medium sized arteries, defined elastic membrane in tunica intima, thick tunica media, thick tunica externa, distribute blood to arterioles

Arterioles (resistance vessels) structure and function 

microscopic, thin tunica intima, few layers of tunica media, collagenous CT and sympathetic nerves in tunica externa, and delivers blood to capillaries and help regulate blood flow from arteries to capillaries