Test 2 Questions Flashcards
What is the tough, superficial layer of the pericardium that helps prevent overstretching of the myocardium?
A) parietal layer of the serous pericardium
B) epicardium
C) fibrous pericardium
D) endocardium
C) fibrous pericardium
The ___ functions to reduce friction between the parietal and visceral layers of the serous pericardium.
A) interatrial septum
B) pericardial fluid
C) auricles
D) sulci
B) pericardial fluid
Which statement is TRUE about the myocardium of the heart wall?
A) The myocardium is innervated by autonomic neurons, which control heart contractions and heart rate
B) All heart chambers exhibit the same myocardium thickness, which allows the heart to be an efficient pump
C) The myocardium of all chambers contract together as a unit, or they do no contract at all
D) The nodes in the myocardium prevent electrical conduction between adjacent cardiac muscle fibers
A) The myocardium is innervated by autonomic neurons, which control heart contractions and heart rate
Which event does NOT occur when the SL valves are open?
A) Blood enters pulmonary arteries and the aorta simultaneously
B) AV valves are closed
C) Ventricles are in diastole and atria are in systole
D) Ventricles are in systole and atria are in diastole
C) Ventricles are in diastole and atria are in systole
Veins of coronary circulation can be described by all of the following except:
A) The vessels drain blood from the small and middle cardiac veins into the coronary sinus
B) These vessels remove deoxygenated blood from the myocardium of the heart
C) The great cardiac vein drains deoxygenated blood from the ventricular myocardium
D) These vessels carry oxygenated blood to the left atrium of the heart
D) These vessels carry oxygenated blood to the left atrium of the heart
The myocardial thickness of the left ventricle is necessary in order to ___.
A) pump blood into the aorta with greater force and pressure
B) pump blood through a smaller valve
C) accommodate a greater volume of blood in the left ventricle
D) expand the atria during systole
A) pump blood into the aorta with greater force and pressure
When is the tricuspid valve closed?
A) during ventricular systole
B) during ventricular diastole
C) during the P-Q interval on an EKG
D) during atrial systole
A) during ventricular systole
Deoxygenated blood pumped from the right ventricle into the pulmonary truck will enter the ___.
A) systemic circulation
B) coronary circulation
C) pulmonary circulation
D) hepatic portal circulation
C) pulmonary circulation
Which statement BEST describes a unique characteristic of autorhythmic fibers?
A) these cells exhibit stable resting membrane potentials
B) these cells only use glucose and fatty acids to synthesize ATP
C) these cells lack striations and abundant mitochondria
D) these cells have gap junctions that allow them to act as functional syncytium
D) these cells have gap junctions that allow them to act as functional syncytium
Which statement is true regarding arteries?
A) the left common carotid artery is an example of a muscular artery
B) arteries always carry oxygenated blood away from the heart
C) elastic arteries function under high blood pressure to stretch rapidly as blood leaves the heart
D) since muscular arteries are located far from the heart, they contain valves to prevent the back flow of blood
C) elastic arteries function under high blood pressure to stretch rapidly as blood leaves the heart
Which statement best describes the tunica externa of a vein?
A) the tunica externa is the endothelial layer of the venous wall that makes contact with the blood
B) the tunica externa is the muscular layer of the venous wall that functions in vasoconstriction
C) the tunica externa is the thickest layer of the venous wall composed of collagen and elastic fibers
D) the tunica externa is the thinnest layer of the venous wall composed of smooth muscle fibers
C) the tunica externa is the thickest layer of the venous wall composed of collagen and elastic fibers
All of the following factors affect blood flow EXCEPT:
A) a decrease in blood viscosity by taking anticoagulants
B) an increase in arterial pressure caused by ventricular systole
C) a decrease in arterial pressure caused by atrial diastole
D) an increase in vascular resistance due to vasoconstriction
C) a decrease in arterial pressure caused by atrial diastole
Which statement correctly identifies one structural difference between arteries and veins?
A) Venous walls are composed of simple squamous epithelium, whereas arterial walls are not
B) Venous walls are composed of a thick layer of smooth muscle fibers, whereas arterial walls are not
C) Arterial walls are composed of a thick layer of smooth muscle fibers, whereas venous walls are not
D) Arterial walls are composed of collagen fibers and venous walls are only composed of elastic fibers
C) Arterial walls are composed of a thick layer of smooth muscle fibers, whereas venous walls are not
Located in the kidneys, ____ are microscopic blood vessels with small pores through their endothelial walls.
A) continuous capillaries
B) arterioles
C) fenestrated capillaries
D) sinusoids
C) fenestrated capillaries
Which statement BEST describes blood flow?
A) blood flow is unaffected by total blood vessel length
B) blood flow increases as vascular resistance increases
C) blood flow is only affected by arterial blood pressure
D) blood flow through the entire systemic circulation is equivalent to cardiac output
D) blood flow through the entire systemic circulation is equivalent to cardiac output
