Exam 3 (Chapters 11-15) Review

Question 1

A. Define cardiac arrhythmias and tachycardia. B. Explain why a patient can lose consciousness if they have tachycardia.

Answer 1

Cardiac arrhythmias are irregular heartbeats. Tachycardia is an abnormally fast heart rate.

Tachycardia causes less time between contractions for the chamber to fill with blood. As a result, over a period of time, the heart fills with less and less blood and thus pumps less blood out. The stroke volume decreases, as does the cardiac output. Loss of consciousness occurs when cardiac output decreases to the point where not enough blood reaches the central nervous system.

Question 2

Explain the physiology behind how malnourishment leads to edema that results in a distended belly.

Answer 2

Malnourishment means a person is not getting enough nutrients, including protein. The lack of sufficient protein means the liver synthesizes fewer plasma proteins, which in turn leads to a decrease in the blood osmotic pressure. Less osmotic pressure at the capillaries leads to filtration exceeding reabsorption, leading to excess fluid accumulating in the interstitium (edema).

Question 3

Explain how medications that block certain antibodies are a treatment for allergies.

Answer 3

Allergies occur when an allergen binds to specific IgE antibodies, which are bound to the surface of mast cells and basophils. A molecule that would bind to the specific IgE for that allergen would block the person’s antibodies to bind, thereby preventing the allergic reaction.

Question 4

Outline the path of a blood cell starting at the left atrium. Include all structures it passes through.

Answer 4

left atrium –> bicuspid (mitral) valve –> left ventricle –> aortic (semilunar) valve –> aorta –> systemic system arteries –> systemic capillaries –> veins –> venea caveae –> right atrium –> tricuspid valve –> right ventricle –> pulmonary (semilunar) valve –> pulmonary trunk –> pulmonary arteries –> pulmonary capillaries –> pulmonary veins –> left atrium

Question 5

What is the chief difference between plasma and serum?

Answer 5

presence or absence of clotting proteins

Question 6

The function of hemoglobin is to…

Answer 6

…bind and transport oxygen and carbon dioxide.

Question 7

Excess transferrins are removed in the _________, where the iron extracted from heme molecules is stored in special protein-iron complexes.

Answer 7

liver and spleen

Question 8

What directly stimulates red blood cell production?

Answer 8

EPO

Question 9

Which condition results from abnormally high levels of bilirubin in the plasma of blood?

Answer 9

jaundice

Question 10

A toxin that blocks the stomach’s ability to release intrinsic factor would most likely cause what?

Answer 10

pernicious anemia

Question 11

Erythropoietin is most likely released under which condition?

Answer 11

during anemia

Question 12

As blood flows through peripheral tissues, what occurs regarding the hemoglobin molecules of RBCs?

Answer 12

Hemoglobin binds carbon dioxide and releases its bound oxygen.

Question 13

A person’s blood type is determined by the…

Answer 13

…presence or absence of specific surface antigens on the plasma membrane.

Question 14

When foreign cells invade the body, one would most likely expect to see increased numbers of what?

Answer 14

lymphocytes

Question 15

A blood clot attached to the wall of a vessel is called a/an ________.

Answer 15

thrombus

Question 16

The common pathway of coagulation ends with…

Answer 16

…the activation of a clotting factor that converts fibrinogen to fibrin.

Question 17

The following is a list of the steps involved in the process of hemostasis and clot removal:

1. coagulation phase
2. fibrinolysis
3. vascular phase
4. retraction
5. platelet phase

What is the correct sequence of these steps?

Answer 17

3, 5, 1, 4, 2

Question 18

According to the Frank-Starling principle, a more powerful contraction results in what?

Answer 18

increased stroke volume

Question 19

The release of norepinephrine at synapses in the myocardium results in what?

Answer 19

an increase in stroke volume

Question 20

The two heart reflexes directly respond to changes in what?

Answer 20

blood volume

Question 21

What permits the exchange of nutrients, dissolved gases, and waste products between the blood and surrounding tissues?

Answer 21

capillaries

Question 22

Compare the average pressure in the right ventricle to the pressure in the left ventricle.

Answer 22

much lower than

Question 23

The function of the cardiac skeleton is to…

Answer 23

…stabilize the position of the heart valves.

Question 24

The QRS complex on an ECG tracing represents what?

Answer 24

ventricular depolarization

Question 25

What is true regarding normal cardiac muscle?

Answer 25

Neither summation nor tetany can occur.

Question 26

The great and middle cardiac veins drain blood directly into the…

Answer 26

…coronary sinus.

Question 27

The amount of blood pumped by the left ventricle in one minute is referred to as what?

Answer 27

cardiac output

Question 28

Why do veins have relatively thin walls?

Answer 28

A typical vein does not need to withstand much pressure.

Question 29

What is the advantage of the small diameter of the capillaries?

Answer 29

It slows blood flow, allowing sufficient time for capillary exchange to occur.

Question 30

________ tend to diffuse across the capillary lining, driven by their individual concentration gradients.

Answer 30

Solute molecules

Question 31

The term blood pressure refers to the pressure in what structure of the cardiovascular system?

Answer 31

the arterial vessels

Question 32

As blood travels through the venous system toward the heart, why do the veins become larger in diameter?

Answer 32

The transition causes the resistance to decrease further so that the flow rate of blood increases.

Question 33

What has the greatest effect on blood flow to the tissues?

Answer 33

peripheral resistance