Blood
What factor contributes most significantly to optimum red blood cell life span?
Small size and membrane flexibility to easily flow through small capillaries
Which cells in the atherosclerotic plaque express scavenger receptors?
Macrophages and foam cells
Non-pacemaker cells of the heart have two periods during which membrane potential is relatively stable. These phases are:
Phases 2 and 4
Which specific key element of the extrinsic pathway is required for a laboratory assay of prothrombin time (PT)?
Tissue factor
What is the earliest blood component to cross the endothelium and enter the intima in the process of atherosclerosis development?
Low-density lipoprotein (LDL)
A person traveling to Africa is prescribed quinine prophylaxis for malaria, and after beginning the drug they develop fatigue and jaundice. Which genetic defect is most likely to account for this development?
Glucose-6-phosphate dehydrogenase (G6PD) deficiency
When constant level of shear stress impacts endothelial cells of the artery lining - what is produced and released?
It stimulates production and release of nitric oxide.
Twenty-four hours after the start of symptoms, which of the following lab values will most directly reflect cardiac damage?
Troponin I
Which endogenous substance inactivates factor V, stopping it from playing its role in the clotting cascade?
Protein C
Which component of the atherosclerotic plaque releases reactive oxygen species (ROS) that oxidize low-density lipoprotein (LDL) particles?
Macrophages
What is the predominant source of bilirubin in the body?
Heme released during RBC breakdown
Name the three layers of the vascular structure
Intima, media, adventitia
What type of heart sound is expected to result from incomplete closing of the mitral valve due to chronic mitral regurgitation?
A murmur beginning just after S1 and ending just after S2
Which chronic disease is most likely to have reduced erythropoietin (EPO) production?
Chronic kidney disease
What is the primary regulator of vasoconstriction, particularly while standing?
Norepinephrine
What accurately describes the mutation responsible for hemoglobin S, the form responsible for sickle cell trait and disease?
Two α chains and two ß chains with a missense mutation replacing a hydrophilic amino acid with a hydrophobic amino acid
The concept that an increase in stretch or wall tension of a blood vessel wall stimulates a compensatory vasoconstriction response:
Autoregulation by the myogenic hypothesis
What electrophysiological consequence of negative dromotropic influences is from the atrioventricular (AV) node?
Heart block
Which biochemical pathway is blocked by the drug warfarin?
Liver synthesis of prothrombin
Which organ/system shows the smallest impact in chronic, poorly managed hypertension?
Gastrointestinal
Which form of anemia results from a primary clotting disorder with excessive clot formation?
Microangiopathic hemolytic anemia
Elastic recoil in the walls of large arteries is the major factor in maintaining which cardiovascular variable?
Diastolic pressure
Which cardiac cycle phase begins with the QRS complex of the ECG?
Isovolumic contraction
What is the initial event reducing blood loss after blood vessel trauma?
Vasoconstriction of the damaged vessel
Which category of antihypertensive drugs is most likely to increase edema formation, particularly in the ankles?
Calcium channel blocking agents