BIO202 - Chapter 20: Blood Vessels and Circulation

Created by angelsheffield 

Upgrade to
remove ads

Arteries

Carry blood away from the heart

Veins

Carry blood back to the heart

Capillaries

Connect smallest arteries to veins

Tunica Interna

Inner lining of arteries, coated with prostacyclin

Tunica Media

Middle, thick layer of arteries; responsible for vasomotion

Vasomotion

Changes in the diameter of the blood vessel brought about by smooth muscle

Tunica Externa

Outermost layer of arteries

Vasa Vasorum

Small vessels that supply blood to at least the outer half of the larger vessels

Conducting Arteries

Largest arteries; Expand during systole, recoil during diastole which lessens fluctuations in blood pressure

Elastic, Large

Other names for Conducting Arteries

Distributing Arteries

Medium arteries; Distribute blood to specific organs

Muscular, Medium

Other names for Distributing Arteries

Resistance Arteries

Small arteries that control amount of blood to various organs

Arterioles

Smallest arteries

Metarterioles

Short vessels that link arterioles to capillaries

Capillaries

Site where nutrients, wastes, and hormones pass between the blood and tissue fluid through the walls of the vessels (exchange vessels)

Continuous Capillaries

Most common capillaries; Tight junctions form a continuous tube with intercellular clefts

Fenestrated Capillaries

Capillaries that are riddled with holes called filtration pores

Sinusoids (Discontinuous Capillaries)

Capillaries with large fenestrations

Thoroughfare Channel

Metarteriole that continues through the capillary bed to the venule

Precapillary Sphincters

Control which capillary beds are well perfused

Capacitance Vessels

Other name for veins

Resistance Vessels

Other name for arteries

Postcapillary Venules

Smallest veins

Large Veins

Veins that feature a thin tunica media with moderate amount of smooth muscle

Heart - Arteries - Arterioles - Capillaries - Venules - Veins

6 Steps of the Simplest & Most Common Circulatory Route (in order)

Portal System

Circulatory route in which blood flows through two consecutive capillary networks before returning to the heart

Anastomoses

Circulatory route where two blood vessels merge

Blood Flow

The amount of blood flowing through an organ, tissue, or blood vessel in a given time

Perfusion

The rate of blood flow per given volume or mass of tissue in a given time

Systolic Pressure

Peak arterial blood pressure

Diastolic Pressure

Minimum arterial blood pressure

120/75

Normal blood pressure

Pulse Pressure

Difference between systolic and diastolic pressure

Mean Arterial Pressure (MAP)

Average of measurements at several intervals throughout the cardiac cycle

Peripheral Resistance

The opposition to flow that blood encounters in vessels away from the heart

Viscosity

Peripheral resistance increases with ____

Blood Flow

Peripheral resistance decreases with ____

Viscosity, Vessel Length, Vessel Radius

3 Things that Affect Peripheral Resistance

Increased

Increased vessel radius produces ___ flow

Capillary Walls

Location of exchanges made between blood and surrounding tissues

Capillary Exchange

Two way movement of fluid across capillary walls

Diffusion, Transcytosis, Filtration, Reabsorption

4 Mechanisms involved in Capillary Exchange

Blood Hydrostatic Pressure

Drives blood out of the capillary

Colloid Osmotic Pressure

Draws fluid into the capillary

Venous Return

The flow of blood back to the heart

Local, Neural, Hormonal

3 Types of Vasomotion Control

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set