3A Blood Vessels Flashcards
What is the term describing the elasticity of the aorta?
Distensible
Where is blood pressure its highest compared to any other vessel?
the ascending aorta
What is the effect where elastic recoil of the aorta helps to dampen/smooth out the pulsitile flow of blood out of the left ventricle?
Wind-kessel effect
What is the TRUE definition of an artery?
Carries blood AWAY from the heart
What are the three layers of an artery?
- Tunica intima (endothelium) 2.Tunica media (muscle) 3.Tunica externa(advetitia)(connective tissue)
What does vasoconstriction do to blood flow?
decrease blood flow
What does vasoconstriction do to resistance?
Increase resistance
What does vasodilation do to resistance?
Decrease resistance
What does vasodilation do to blood flow?
Increase blood flow
What are the four methods of changing the radius of an arteriole?
- Autonomic Nervous System (Epi/NorEpi) 2. Hormones (Angiotensin II, Vasopressin) 3. Local Substances (NO) 4.Other (temperature)
Which vessels have the GREATEST TOTAL cross sectional surface area?
Capillaries!
What are the two structural components of a capillary?
1.Single layer of endothelial cells 2.basement membrane
What is another name for the small pores of the endothelial cell?
Fenestrations
What is the true definition of a vein?
Carries blood TOWARDS the heart
Which vessel contains the highest proportion of blood in the cardiovascular system at any given time?
veins!
