Exam 1 Flashcards
Inflammatory pathways promote thrombosis, which is responsible for myocardial infarction and most strokes?
True or False
True
Ischemia is most responsible
What is released from the endothelial wall, that promotes vasodilation and limits platelet extension? A. thromboxane A2 B. prostaglandin F 2 a C. prostacyclin (PGI2) D. norepinephrine
C. prostacyclin (PGI2)
Thromboxane A2 vasoconstricts and produced by platelets
A traumatized vessel will constrict; most of the constriction is due to which of the following?
A. SNS reflex contraction
B. thromboxane A2 release from platelets
C. local myogenic spasm
D. prostacyclin release from the endothelium
C. local myogenic spasm
Which of the following is effective at dissolving blood clots? A. plasmin B. throboxane A2 C. prostacyclin D. heparin
A. plasmin
Heparin prevents clots from forming
What is the key step in blood coagulation?
A. release of platelet granule contents
B. activation of factors X and V
C. sympathetic stimulation of vascular smooth muscle
D. conversion of fibrinogen to fibrin
D. conversion of fibrinogen to fibrin
requires thrombin
Fibrinogen and prothrombin along with factors VII, IX, X are produced by which organ? A. liver B. lungs C. spleen D. kidney
A. Liver
Concerning Ca++ role in blood clotting, which of the following statements is true?
A. required at all intrinsic pathway steps
B. only required at all extrinsic pathway steps
C. required at all steps except the 1st two intrinsic steps
D. required only to allow thrombin to convert fibrinogen to fibrin
C. required at all steps except the 1st two intrinsic steps
required at all extrinsic steps
Compared to a typical ventricular muscle cell, which of the following is a characteristic of the SA node?
A. only fast Na+ channels operational
B. longer plateau
C. lacks a stable resting polarized state
D. more negative resting membrane potential
C. lacks a stable resting polarized state
SA node leaks ions
AV delayed wave and SA fastest
At a normal resting membrane potential of -85 mV, which of the following ions is closest to its Nernst equilibrium potential? A. Na+ B. Ca++ C. K+ D. Cl-
C. K+
A 2-3 X elevation in extracellular fluid of what ion can cause flaccidity and weakness of cardiac muscle in part by decreasing the resting membrane potential A. Na+ B. Ca++ C. K+ D. Cl-
C. K+
If end diastolic volume = 160 ml and end systolic volume = 120 ml; what is the ejection fraction? A. 25% B. 50% C. 75% D. undeterminable
A. 25%
100 X 40/160 = 25%
normal = 50%-60%
The aortic valve opens at what point? (on graph drawing) A. A B. B C. C D. D
B. B
The mitral valve opens at what point? (on graph drawing) A. A B. B C. C D. D
D. D
Emptying of the ventricle occurs between what two letters? (on heart drawing) A. AB B. BC C. CD D. DA
C. CD
Isovolumic relaxation occurs between what two letters? (on heart drawing) A. AB B. BC C. CD D. DA
D. DA
What percentage of blood from the atrial to the ventricle is actively pumped? A. 25%-30% B. 45%-55% C. 70%-75% D. 95%-100%
A. 25%-30%
70%-75% passive