Intro to Circulatory System of Upper Extremity Flashcards
Definition: arteries
Blood moves away from the heart
Arteries branch to form
arterioles
Arterioles size:
less than 0.5mm diameter
Arterioles disperse O2 and nutrients into:
capillaries
Diffusion takes place in
capillaries
Waste products picked up by
venules
Venules joint to form larger vessels:
veins
Explain the layers of an artery
- Tunica Intima (Interna)
- inner layer (squamous epithelium)
- inner wall form the hole (lumen)
- attached by connective tissue to the middle layer - Tunica Media
- thick intermediate layer (smooth muscle + elastic tissue) - Tunica externa (Adventitia)
- Outermost fibrous layer
- can contain smooth muscle
- similar to serous layer except it’s anchored to surrounding structures
Arteries are flexible due to
flexibility of Tunica media
What is arteriosclerosis
When arteries harden with age
- inc. BP with dec. distention
What is atherosclerosis
lumen narrowing due to deposition of fat on walls
Risks of arteriosclerosis and atherosclerosis
Heart attack or stroke
What is anastomosis
- connecting arteries (e.g. PHC and AHC)
- small adjacent arteries form to accommodate blood flow
- collateral circulation
What is the circle of willis an example of?
Anastomosis
What is the most important part of the circulatory system?
Capillary Bed!! (no smooth muscles on walls!)