Non-AI Lecture 18

What are the components of the cardiovascular system

heart, arteries, veins, blood (transport medium)

What is the function of the components of the cardiovascular system

deliver substances to the tissues (glucose, O2) and remove metabolic waste byproducts (co2, lactate, heart)

What is the order of vessel hierarchy

arteries, arterioles, capillaries, venules, veins

carry blood at low pressures, under control of the ANS, thin layers of muscle

Veins

carry blood at high pressure, thick muscular wall, limited expansion

Arteries

carry blood at modest pressure, faucets to control flow to tissues

Arterioles

Carry blood at low pressure, maximize exchange of material between the blood and cells

Capillaries

Tunica _____ → innermost layer
Tunica _____ → middle/medial layer
Tunica _____ → outermost/external layer

intima, media, externa

Large arteries that contain more elastic fibers but to being under high pressure, they absorb energy and stretch

Elastic arteries

Smaller arteries/arterioles that contain more muscle fibers for vasoconstriction and vasodilation

Muscular arteries

aka resistance vessels, called this due to a small radius that creates greatest resistance to blood flow. The largest pressure drop in systemic circulation

Arterioles

aka exchange vessels

capillaries

What are some ways that substances are exchanged through capillaries

junctions btwn endothelial cells, fenestrations, diffusion, active transport

capillaries are the site of exchange of whar

nutrients, waste products, and fluids

capillaries are ________ and allow for the exchange of solutes and gases

thin-walled

low pressure structures that hold the majority of blood volume (60-70%)

Veins (capacitance vessels)

veins are thin walled, fibrous, and have a _____ diameter

large

pushes blood back to the heart, activates and contracts with movement

muscle pump

What are three things that aid in venous return

muscle pumps, valves, & breathing