Exam 3 (Chapters 11-15) Review Flashcards
A. Define cardiac arrhythmias and tachycardia. B. Explain why a patient can lose consciousness if they have tachycardia.
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.
Explain the physiology behind how malnourishment leads to edema that results in a distended belly.
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).
Explain how medications that block certain antibodies are a treatment for allergies.
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.
Outline the path of a blood cell starting at the left atrium. Include all structures it passes through.
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
What is the chief difference between plasma and serum?
presence or absence of clotting proteins
The function of hemoglobin is to…
…bind and transport oxygen and carbon dioxide.
Excess transferrins are removed in the _________, where the iron extracted from heme molecules is stored in special protein-iron complexes.
liver and spleen
What directly stimulates red blood cell production?
EPO
Which condition results from abnormally high levels of bilirubin in the plasma of blood?
jaundice
A toxin that blocks the stomach’s ability to release intrinsic factor would most likely cause what?
pernicious anemia
Erythropoietin is most likely released under which condition?
during anemia
As blood flows through peripheral tissues, what occurs regarding the hemoglobin molecules of RBCs?
Hemoglobin binds carbon dioxide and releases its bound oxygen.
A person’s blood type is determined by the…
…presence or absence of specific surface antigens on the plasma membrane.
When foreign cells invade the body, one would most likely expect to see increased numbers of what?
lymphocytes
A blood clot attached to the wall of a vessel is called a/an ________.
thrombus
The common pathway of coagulation ends with…
…the activation of a clotting factor that converts fibrinogen to fibrin.
The following is a list of the steps involved in the process of hemostasis and clot removal:
- coagulation phase
- fibrinolysis
- vascular phase
- retraction
- platelet phase
What is the correct sequence of these steps?
3, 5, 1, 4, 2
According to the Frank-Starling principle, a more powerful contraction results in what?
increased stroke volume
The release of norepinephrine at synapses in the myocardium results in what?
an increase in stroke volume
The two heart reflexes directly respond to changes in what?
blood volume
What permits the exchange of nutrients, dissolved gases, and waste products between the blood and surrounding tissues?
capillaries
Compare the average pressure in the right ventricle to the pressure in the left ventricle.
much lower than
The function of the cardiac skeleton is to…
…stabilize the position of the heart valves.
The QRS complex on an ECG tracing represents what?
ventricular depolarization
What is true regarding normal cardiac muscle?
Neither summation nor tetany can occur.
The great and middle cardiac veins drain blood directly into the…
…coronary sinus.
The amount of blood pumped by the left ventricle in one minute is referred to as what?
cardiac output
Why do veins have relatively thin walls?
A typical vein does not need to withstand much pressure.
What is the advantage of the small diameter of the capillaries?
It slows blood flow, allowing sufficient time for capillary exchange to occur.
________ tend to diffuse across the capillary lining, driven by their individual concentration gradients.
Solute molecules
The term blood pressure refers to the pressure in what structure of the cardiovascular system?
the arterial vessels
As blood travels through the venous system toward the heart, why do the veins become larger in diameter?
The transition causes the resistance to decrease further so that the flow rate of blood increases.
What has the greatest effect on blood flow to the tissues?
peripheral resistance
