24th November, 2011

Textbook Page - 180

What are Blood Vessels?

A part of the circulatory system that transports

blood throughout the

body.

Word Element Refers toAort/o Aorta

Arteri/o Artery Phleb/o Vein

Veno VeinAngi/o VesselVas/o Vessel

Vascul/o Blood vessels-emia Blood

Hem/o , hemat/o Blood Coron/o Crown; encircling such as in the

coronary blood vessels encircling the heart

Dilate To open up a hollow structureEctasis Dilation

Constrict To narrow a hollow structure

Network of vessels that transport blood throughout the body.

Arteries Capillaries Veins • Thick-walled • Elastic • Carry oxygenated blood

away from the heart to different organs (except pulmonary arteries, they carry deoxygenated blood)

Arterioles:• Small branches of the

arteries • Carry oxygenated blood to

capillaries• Regulate blood

distribution to various tissues of the body

• Connect arterial and venous system

• One cell thick• Responsible for the

exchange of gases and nutrients with the tissues

• Return deoxygenated blood to the heart (except pulmonary veins carry oxygenated blood).

• Have valves that permits one directional flow

Venules: • Smaller branches of veins • Receive blood from the

capillaries and transport it to the veins

• Lumen of a blood vessel is the opening through which blood flows • The nervous system can stimulate the lumen to be more open called vasodilation or more

closed called vasoconstriction.• Together these form a closed delivery system of vessels for delivering oxygen and nutrients

to body cells, also removes waste products.

ARTERIES• Blood is ejected out at a high

velocity and with high pressure

• Walls have to be strong (to withstand the pressure), elastic and muscular.

• Walls dilate when the pressure pushes outwards, and later bounce back to normal shape

• This ‘bounce’ commonly known as ‘’the pulse’’ is felt in some areas of our body such as at the wrist.

VEINS• The vein wall has the

same layers as the arterial wall, but it is much thinner.

• Low Pressure

• Smooth Flow when we are lying down at rest.

DIRECTION OF BLOOD FLOW

REQUIRED TERMINOLOGY

DISEASE MEANINGAneurysm A localized dilation of an artery or other vessel

Angiospasm Spasm in blood vessels

Angiostenosis Narrowing of a blood vessel

Arteriospasm Spasm of an artery

Arteriostenosis Narrowing of an artery

Arteritis Inflammation of an artery/arteries

Atheroma Fatty deposit/plaque within arterial walls

Atrial fibrillation Rapid, ineffective contraction of the atrium

Disseminated Intravascular Coagulation(DIC)

Widespread clotting in the blood vessels causing obstruction to the tissues

Dyscrasia General term for blood disorder

Thrombus Blood Clot attached to an interior wall of a vein or an artery

Cardiac Catheterization Procedure where a catheter is inserted into the heart. This is used for the diagnosis of blockages and their

treatments.

Statins A type of cholesterol lowering drug

Stent Device implanted into the artery to open and provide support to the arterial wall.

SUMMARY OF THE VASCULAR SYSTEM

TEXTBOOK PAGE - 180