A&p Test 3 - Blood Vessels

Front 1

You should consider what three main factors when thinking of how blood pressure is regulated?

Back 1

Cardiac Output, Peripheral Resistance, Blood Volume

Front 2

In homeostatic management, when one factor decreases, typically, feedback mechanisms elecate the other two parameters to get blood pressure back up to that "magic number" programmed for that activity level -- even if the programmed number is too high. This presents problems in the management of what? Why?

Back 2

Hypertension; as soon as you decrease one factor with drugs, the others go up, elevating blood pressure again.

Front 3

Pulse wave and blood pressure decrease as you get further from the heart, T/F

Back 3

T

Front 4

__________ __________ is the most significant type of resistance and is the resistance that the blood encounters due to it's friction against the walls of the vessels.

Back 4

Peripheral Resistance

Front 5

Peripheral resistance is influenced by what 3 factors?

Back 5

Blood viscosity, Vessel length, Vessel Radius

Front 6

Blood viscosity is mostly due to what two things?

Back 6

Plasma proteins, erythrocytes

Front 7

What is the most abundant plasma protein? Erythrocytes are the most numerous what?

Back 7

Albumin, Formed element

Front 8

Blood with fewer solutes/cells flows more rapidly than blood with more solutes cells. T/F

Back 8

T

Front 9

Blood viscosity is likely to change. T/F

Back 9

F

Front 10

In regards to vessel length, the longer the tube, the greater the?

Back 10

Resistance to fluid moving through it

Front 11

Vessel length does not change from moment to moment. It will change however, with with large ______ ____ and _____ and can, in that respect, influence ______ ______.

Back 11

Weight gains and losses; blood pressure

Front 12

Often people who are hypertensive and obese are advised to do what? Why?

Back 12

Lose weight to reduce vessel length

Front 13

That is the most important (and rapidly variable) factor in determining resistance?

Back 13

Vessel radius

Front 14

In regards to vessel radius, based on the activity of the _______ (mostly sympathetic) nervous system, _________ can change nearly instantly. Numerous hormones and other agents can also produce _______/________. This does, therefore, change from moment to moment as a normal part of homeostatic regulation that aids in delivering blood to rapidly metabolizing tissues by?

Back 14

In regards to vessel radius, based on the activity of the AUTONOMIC (mostly sympathetic) nervous system, VESSEL DIAMETER can change nearly instantly. Numerous hormones and other agents can also produce VASOCONSTRICTION/DIALATION. This does, therefore, change from moment to moment as a normal part of homeostatic regulation that aids in delivering blood to rapidly metabolizing tissues by SHUNTING BLOOD FLOW FROM LESS ACTIVE AREAS.

Front 15

A tiny arteriole can constrict down to ______ or less of it's original diameter (remember, the ______ is to the fourth power!)

Back 15

one third; radius

Front 16

What controls blood flow in a given area from moment to moment based on local chemical conditions?

Back 16

Autoregulation

Front 17

Autoregulation is an example of what kind of control?

Back 17

Local control

Front 18

If autoregulation fails, what happens? This is an example of what kind of control?

Back 18

The nervous system (specifically the sympathetic branch of the autonomic n.s) becomes involved and rapidly acts in an attempt to correct homeostasis; Neural control

Front 19

Vasomotor centers are located near the ______ _____ in the _____ _____. Sometimes these centers are collectively referred to as the ______ ______.

Back 19

cardiac centers; medulla oblongata; cardiovascular centers

Front 20

Most blood vessels _______ with sympathetic stimulation. Blood vessels supplying skeletal muscle _____ under sympathetic stimulation. Why?

Back 20

constrict; dialate; So you can fight or flight.

Front 21

The vasomotor centers constantly fire at a _______ rate, maintaining "______", (a moderate degree of vasoconstriction) and keeping the vascular compartment as a whole, matched to our normal ______ _____.

Back 21

moderate, "vascular tone", blood volume

Front 22

When the baroreceptors are stretched and blood pressure is too high, feedback mechanisms cause ______ to drop. (____________ center is _______ and ________ center is _______.)

Back 22

CO; CARDIOACCELERATORY CENTER is INHIBITED and CARDIOINHIBITORY CENTER is STIMULATED.

Front 23

When the baroreceptors are stretched and blood pressure is too _____, ________ _______ cause CO to drop.

Back 23

high; feedback mechanisms

Front 24

When the baroreceptors are stretched and blood pressure is too high, feedback mechanisms cause CO to drop. (Cardioacceleratory center is inhibited and Cardioinhibitory center is stimulated). The vasomotor centers also fire less, thus?

Back 24

Lowering blood pressure

Front 25

In regards to baroreceptors, the opposite feedback occurs when there is too little ______ and the _______ is too low.

Back 25

stretch, blood pressure

Front 26

In regards to baroreceptors, the ______ ______occurs when there is too little stretch and the blood pressure is too low.

Back 26

opposite feedback

Front 27

In regards to baroreceptors, the opposite feedback occurs when there is too little stretch and the blood pressure is too low. These feedback mechanisms function to perform what? Give an example.

Back 27

Short term corrections, such as when we change posture.

Front 28

These respond to blood chemistry changes by adjusting respiration, CO, and vasomotion. Give two examples.

Back 28

Chemoreflexes; Aortic bodies and Carotid bodies.

Front 29

Chemoreflexes respond to what three things? Where are they located? If any of these occur, feedback response is to do what? The most sensitive chemoreceptors are?

Back 29

Low pH, High carbon dioxide levels, Low oxygen levels; In the major arteries and medulla oblongata; Any one or combination of these conditions will activate feedback response is to increase blood pressure/CO. Most sensitive to decrease in pH and increase in carbon dioxide.

Front 30

Specific reflex that protects the brain during sudden drops in perfusion rate there through initiation of widespread vasoconstriction and increases in HR and SV.

Back 30

Medullary Ischemic Reflex.

Front 31

Medullary Ischemic Reflex: Specific reflex that protects the brain during what? What does it do to protect it?

Back 31

Sudden drops in perfusion rate there through initiation of widespread vasoconstriction and increases in HR and SV.

Front 32

Homeostatic regulation of blood volume usually involves the ______ ______ and is a more ______ _____ means of control

Back 32

endocrine system; long term