A & P 2 Chapter 19 - The Cardiovascular System

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Terms in this set (...)

Aterties
Carry blood away from the heart
What happens if you cut an artery?
It will spurt bright red blood
Capillaries
Contact tissue cells and directly serve cellular needs.
Veins
Carry blood towards the heart.
T/F you can feel your pulse in an artery?
True
T/F you can feel your pulse in a vein?
False
Lumen
Central blood containing space
Tunica Media
-Smooth muscle and sheets of elastin
-Sympathetic vasomotor nerve fibers control vasoconstriction and vasodilation of vessels.
Vasoconstriction
Constricts-Closes
Vasodilation
Relaxes-Opens
Elastic Arteries are what kind of arteries?
Conducting
Elastic Arteries
Large thick-walled arteries with elastin in all 3 tunics
What is an elastic artery?
The aorta
What kind of resistance does the large lumen offer?
Low resistance
What kind of arteries are distributing arteries?
Muscular Arteries
Where do muscular arteries and arterioles deliver blood?
-Distal to elastic
-Deliver blood to body organs
Arterioles
The smallest arteries
Capillaries
Walls of thin tunica intima/one cell thick
Where are capillaries located?
In all tissue EXCEPT cartillage, epithelia, cornea, and lens of eye.
What do capillaries do?
They exchange gasses, nutrients, wastes, hormones, etc.
Continuous capillaries of the brain
Tight junctions are complete, forming the blood-brain barrier.
Fenestrated capillaries
Leaky capillaries (contain pores)
Where are fenestrated capillaries located?
-Small intestines
-Endocrine glands
-Kidneys
Sinusodial Capillaries
-VERY leaky capillaries
-Allow large molecules and blood vessels to pass between the blood and surrounding tissues.
Where are sinusoidal capillaries found?
-Liver
-Bone marrow
-Spleen
What regulates blood flow into true capillaries?
Precapillary sphincters
Venules
-Formed when capillary beds unite
-Very porous; allow fluids and WBCs into tissues
When are veins formed?
When venules converge
Veins
-Have thinner walls, larger lumens compared with corresponding arteries
What is blood pressure like in veins in comparison to arteries?
Blood pressure is lower in veins than in arteries
Capacitance vessels (blood reservoirs)
Veins
How much of the blood supply do veins consist of?
65%