Unit 1. Lec 4-Control of Blood Flow & Microcirculation Flashcards
What are blood vessels for?
Delivery of nutrients, removal of waste
How do blood vessels deliver nutrients to the tissues?
Microvascular Exchange-a consequence of vessel permeability
Mainly capillaries
True or False. All blood vessels are perfused all the time
False
How does our body determine which blood vessels to perfuse?
Body prioritizes blood flow to metabolically active organs
e.g. brain, heart
What vessel type accounts for the highest surface area (cross-sectional area)?
Capillaries
What vessel type accounts for the lowest blood velocity?
Capillaries
Why do capillaries have the highest surface area and lowest velocity?
- Highest SA-so they have amble space to exchange nutrients
- Lowest Velocity-so they can have time for exhange to occur
Capillaries are known as the “exhange vessel”
How much of our blood is located in our veins and why?
65% (most of it) b/c veins have low capacitance and high compliance
- Capillaries are “______ vessels”
- Veins are ________vessels”
- Arterioles are _______vessels”
- Exchange- low velocity, low blood volume
- Capacitance-high blood volume
- Resistance-largest pressure drop
Role of Arterioles
Resistance vessels- regulate systemic vascular resistance (SVR) aka total peripheral resistance
What does the Arterioles control?
Simultaneously control SVR and blood flow to tissues
