A person has atrial septal defect [hole in the interatrial septum]. This would result in the abnormal flow of blood from:
1. the right side of the heart to the left
2. the left side of the heart to the right
3. the pulmonary artery to the aorta
4. the ductus arteriosus to the aorta

The plateau in the cardiac action potential is primarily due to:
1. slow outward diffusion of ${\mathrm{K}}^{+}$
2. fast inward diffusion of ${\mathrm{Cl}}^{-}$
3. fast outward diffusion of ${\mathrm{Ca}}^{2+}$
4. slow inward diffusion of ${\mathrm{Ca}}^{2+}$

The fraction of an anticoagulated blood sample called the "buffy coat" contains
1. red blood cells
2. white blood cells
3. platelets
4. white blood cells and platelets

The cause of “aplastic anemia" would be:
1. lack of iron content or iron absorption from the diet
2. destruction of the bone marrow, perhaps by chemicals in the environment or chemotherapy
3. high altitude
4. inadequate vitamin B₁₂ absorption from the diet because the intrinsic factor is absent

Veins are said to have a higher ____ than arteries because they expand more easily and a higher ___________ because they contain more blood.
1. compliance; capacitance
2. elasticity; compliance
3. elasticity; capacitance
4. None of the above

Severe dyspnea due to pulmonary edema will be caused most likely by:
1. cardiogenic shock
2. anaphylactic shock
3. right-sided congestive heart failure
4. left-sided congestive heart failure

Atria can completely empty during ventricular filling due to:
1. A-V node
2. A-V bundle
3. S-A node
4. Purkinje fibers

The arrhythmia that results in cardiac arrest followed by death in the absence of treatment and therefore considered most serious is:
1. Tachycardia
2. Sinus bradycardia
3. Atrial flutter
4. Ventricular fibrillation

The least significant factor for erythropoiesis amongst the following is:
1. vitamin B₁₂
2. vitamin B₆
3. folic acid
4. gastric intrinsic factor

Also sometimes called as the ‘widow maker’ the anterior interventricular artery is a branch of the
1. left circumflex artery.
2. right anterior descending artery.
3. left coronary artery.
4. right coronary artery.