CVS and Lymph Study Guide

Question 1

What is the function of the CVS?

Answer 1

Transport nutrients, water, gases from external environment, cell-to-cell transport, waste

Question 2

What is pulmonary and systemic circulation?

Answer 2

Blood picks up O2 from the lungs and nutrients from intestines and simultaneously removes waste

Question 3

What is hydrostatic pressure?

Answer 3

The pressure that blood exerts on the walls of blood vessels, generating blood pressure

Question 4

What divides the heart into right and left halves?

Answer 4

The septum

Question 5

Blood flows down _____.

Answer 5

pressure gradients

Question 6

The mean BP ranges from a high ____ mm Hg in the _____ to a low of a ____ mm Hg in the _______.

Answer 6

93; aorta; few; venae cava

Question 7

What can be said about pressure?

Answer 7

It falls over distance as energy is lost due to friction.

Question 8

Pressure is created by contracting muscles and transferring that pressure to blood. True or False.

Answer 8

True

Question 9

The _____ the pressure gradient, the greater the fluid flow.

Answer 9

higher

Question 10

What ventricle creates the driving pressure for systemic flow?

Answer 10

The left

Question 11

If blood vessels constrict, _____ increases.

Answer 11

blood pressure

Question 12

If blood vessels dilate, ______ decreases.

Answer 12

blood pressure

Question 13

True or False. Volume changes do not affect blood pressure in the cardiovascular system.

Answer 13

False. It greatly affects blood pressure.

Question 14

What do baroreceptors do?

Answer 14

They send signals about blood pressure.

Question 15

What are baroreceptors most concerned with?

Answer 15

Decreasing blood pressure.

Question 16

Although the baroreceptors can respond to either an increase or decrease in systemic arterial pressure, what is their most important role?

Answer 16

Responding to sudden reductions in arterial pressure, such as a hemorrhage.

Question 17

What results from a decrease in arterial firing?

Answer 17

Decreased baroreceptor firing.

Question 18

What responds to baroreceptors (in the brain)?

Answer 18

Autonomic neurons within the medulla oblongata respond by increasing sympathetic and decreasing parasympathetic outflow.

Question 19

What are some reasons in sudden drop in blood pressure?

Answer 19

dehydration, bleeding, drugs, anesthesia

Question 20

What does the brain do when it senses a drop in blood pressure?

Answer 20

Will send signals to kidneys to stop urine production, reduce blood flow to some organs

Question 21

What is an aortic valve stenosis?

Answer 21

Occurs when the heart’s aortic valve narrows. It prevents the valve from opening fully, which reduces or blocks blood flow fromt he heart into the aorta.

Question 22

What are contractile cells?

Answer 22

Striated with sarcomere organization, smaller and have single nucleus per fiber, have intercalated disks

Question 23

What provides electrical connection between contractile cells?

Answer 23

Gap junctions

Question 24

What is congestive heart failure?

Answer 24

A chronic condition that causes fluid to build up around the heart making the heart unable to pump efficiently. It develops when ventricles can’t pump enough blood volume to body.

Eventually, blood and other fluids can back up inside the lungs, abdomen, liver and lower body.

Question 25

What is mitral valve regurgitation?

Answer 25

The heart's mitral valve doesn't close tightly, allowing blood to flow backward into the heart. It can make patients feel tired and out of breath.

Question 26

How long is the refractory period in cardiac muscle?

Answer 26

Almost as long as a muscle twitch.

Question 27

What does a long refractory period do? Why is this a good thing?

Answer 27

It prevents tetanus, which is sustained contraction. A heart in tetany can not pump blood. A longer refractory period ensures that the heart cannot contract twice in a row too quickly.

Question 28

What is pacemaker potential?

Answer 28

The heart doesn't "rest" at a set value, funny channels slowly leak Na+, net influx of positive charge slowly depolarizes cell to threshold.

Question 29

What do electrical conduction in myocardial cells depend on?

Answer 29

gap junctions

Question 30

True or False. All myocardial cells must contract in a coordinate fashion to create enough force to circulate the blood.

Answer 30

True.

Question 31

What does the AV node do?

Answer 31

Routes the direction of electrical signals, delays the transmission of action potentials.

Question 32

What does the SA node do?

Answer 32

Sets the pace of the heartbeat at 70 bpm.

Question 33

AV node (____BPM) and Purkinje fibers (_____BPM) can act as _______ under some conditions.

Answer 33

50 BPM; 25-40BPM; pacemakers

Question 34

What does the bundle branch block do?

Answer 34

Blocks conduction

Question 35

What are the pacemakers of the heart?

Answer 35

SA node - dominant pacemaker with intrinsic rate of 60-100 BPM AV node - back-up pacemaker with intrinsic rate of 40-60 BPM Ventricular cells - back-up pacemaker with intrinsic rate of 20-45 BPM

Question 36

How does the parasympathetic system control the heart?

Answer 36

The overall goal is to reduce heart rate. This is done by: It is controlled by the Vagus nerve (CN X) and reduces heart rate. Baroreceptors in the aorta and carotid signal the brain about blood pressure, which releases acetylcholine at the SA node - increasing permeability to K+ and decreases the firing rate of the SA node

Question 37

How does the sympathetic system control the heart?

Answer 37

Sympathetic control of the heart is caused by stress, exercise, and increases HR. Norepinephrine is releases which increases permeability of myocardial cells to Na+, and Ca2+. Decreases threshold potential of SA node - fires more rapidly, faster conduction time.

Question 38

How do you calculate mean arterial pressure? What affects mean arterial pressure?

Answer 38

Cardiac output x peripheral resistance Distance, viscosity, diameter

Question 39

How do capillary filtration and absorption take place?

Answer 39

Via bulk flow (velocity of blood flow lowest at capillaries)

Question 40

What is bulk flow?

Answer 40

Mass movement as a result of hydrostatic or osmotic pressure gradients

Question 41

What is absorption?

Answer 41

Fluid movement into capillaries with a net absorption at venous end

Question 42

What is filtration?

Answer 42

Fluid movement out of capillaries which is caused by hydrostatic pressure and a net filtration at arterial end

Question 43

What is the role of the lymphatic system?

Answer 43

Return fluid and proteins to circulatory system, pick up fat absorbed at small intestine and transfer it to circulatory system, serve as filter to help capture and destroy pathogens, waves of contraction of smooth muscle in larger lymph vessels

Question 44

What is edema?

Answer 44

Accumulation of fluid in interstitial place - inadequate drainage of lymph

Question 45

True or False. In a pulmonary circuit, hydrostatic pressure is lower so less fluid is lost from capillaries.

Answer 45

True

Question 46

Increasing blood pressure due to more blood in right ventricle leads to what?

Answer 46

Greater fluid loss in lung capillaries.

Question 47

What is pulmonary edema? What are some treatment options?

Answer 47

Vascular resistance of pulmonary circuit is low so BP in pulmonary circuit is lower. With higher blood pressures created by increased blood volume, there is more loss of fluid out of capillaries - this leads to fluid surrounding the alveoli in the lungs, congestion and poor O2 and CO2 exchange - and thus, increases HR. Treatment options: diuretics and vasodilators

Question 48

What happens when there is a disruption of balance between filtration and absorption?

Answer 48

Increases capillary hydrostatic pressure, and decreases plasma protein concentration (caused by severe malnutrition or liver failure).