Chapter 14 test yourself
How could mitral valve stenosis affect the stroke volume?
Decrease stroke volume because the valve is not opening all the way so less blood is being delivered to the ventricle. In other words, the preload will decrease.
The coronary artery is the first branch off the aorta. Is it a muscular or elastic artery? Why?
Elastic because it has to be able to withstand the high pressure of the blood leaving the left ventricle via the aorta
When the mitral valve is forced closed it produces part of which heart sound, the first or the second?
First sound; the sound of the AV valves closing
What two bypass structures are found in the fetus that allow most of its blood to bypass the pulmonary circulation?
Foramen ovale and ductus arteriosus
List three structures found in the mediastinum
Heart, trachea, esophagus, thymus, lymph nodes, nerves
Stroke volume (SV) is a measurement of what?
Amount of blood ejected from the left ventricle during one contraction
From the aortic valve in the left ventricle to the right atrium, list, in order, the types of blood vessel a drop of blood will pass through.
Aorta, large to small elastic arteries, large to small muscular arteries, arterioles, capillaries, venules, small to large veins, vena cava, right atrium
List, in order, the structures on erythrocyte will pass through (including valves) to move in a complete circuit from the left ventricle back to the left ventricle.
Aortic valve, aorta, systemic circulation, vena cava, right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary circulation, left atrium, mitral valve, left ventricle
Which type of blood vessel carries blood away from the heart? Toward the heart?
Arteries carry blood away from the heart; veins carry blood toward the heart.
Why is the wall of the right ventricle thinner than the wall of the left ventricle?
Because the right ventricle doesn't have to pump as hard to get blood into pulmonary circulation as the left ventricle does to get blood into systemic circulation
What is the name of the structure that is a continuation of the myocardium that forms a wall between the two atria? The two ventricles?
Interatrial septum; interventricular septum
What is happening in the other three heart chambers during left atrial diastole?
Right atrial diastole, right and left ventricular systole
List the four conductors that make up the rapid conduction system for an impulse created by the heart's pacemaker.
SA node, AV node, bundle of His, Purkinje fiber system
What is the pacemaker of the heart and where is it located?
SA node, wall of the right atrium
The working phase of a cardiac cycle is __________. It involves __________ that generates an impulse that results in muscle contraction.
Systole, depolarization
What is the difference between an ECG and an ECHO?
The ECG detects the electrical activity in the heart and is used to evaluate the cardiac conduction system; the ECHO uses ultrasound waves bounced off the heart to evaluate size, shape, and movement of the heart. Doppler ECHO evaluates blood flow in the heart.
Which is located more caudally in a standing pig, the apex or the base of the heart?
The apex
Which vein can be used in most common animal species for venipuncture? Where is it located?
The bilateral jugular veins located in jugular grooves on the ventral aspect of the neck from the mandible to the shoulder
What is the difference between the endocardium and the pericardium?
The endocardium is the membrane that lines the chambers of the heart. It lies on the internal surface of the myocardium; the epicardium lies on the external surface of the myocardium and is synonymous with the visceral layer of the serous pericardium.
What is the difference between a heart rate and a pulse?
The heart rate measures the number of ventricular contractions in 1 minute; the pulse measures the rate of alternating stretching and recoiling of an elastic artery wall as blood passes through it over 1 minute.
If the cardiac output and stroke volume both decrease what has to happen to the heart rate to achieve equilibrium?
The heart rate will have to increase.
Which sits closer to the base of the heart, the left atrium or the right ventricle?
The left atrium
What is the difference between the preload and the afterload in reference to the stroke volume?
The preload is the amount of blood the ventricle receives from the atrium; the afterload is the amount of physical resistance presented by the aorta.
What does systolic blood pressure measure?
The pressure produced in an artery by the blood ejected from the left ventricle during systole
What are the two parts of the cardiovascular system? Which part carries blood to and from the left rear leg of a pony?
The pulmonary circulation and the systemic circulation. The systemic circulation.
In a pregnant ewe, which are the only two veins that are carrying oxygenated blood?
The pulmonary vein that carries oxygenated blood to the left atrium from the pulmonary circulation and the umbilical vein that carries oxygenated blood from the mother to the fetus.
What is the function of the chordae tendonae?
To prevent the AV valves from opening backward into atria
What is another name for each of these valves: right AV valve, semilunar valve in the right ventricle, left AV valve, semilunar valve in the left ventricle?
Tricuspid valve, pulmonary valve, mitral or bicuspid valve, aortic valve
