When a blood vessel gets injured, the first event to occur in hemostasis is:
1. The endothelial lining is damaged, exposing collagen proteins to the blood.
2. The injured blood vessel is dilated by newly released chemicals to let in defense cells.
3. Platelets become "sticky" and a platelet plug is formed near the injury site.
4. A web of fibrin protein strands tightly interweave the platelet plug.

Which of the following ions is vital for coagulation of blood?

What is the average duration of diastole and systole in a cardiac cycle lasting 0.8 seconds?
1. 0.3 seconds; 0.5 seconds
2. 0.4 seconds; 0.4 seconds
3. 0.5 seconds; 0.3 seconds
4. 0.6 seconds; 0.2 seconds

How would the right heart compared to the left during one cardiac cycle?
1. left heart pumps a lesser volume of blood than the right heart
2. right heart contracts shortly before the left heart
3. right heart pumps blood with less force (at lower pressure) than the left heart
4. left heart has a shorter cardiac cycle duration than the right heart

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 ${\mathrm{Ca}}^{2+}$

Artificial pacemakers can be used to treat a patient suffering from:
1. a myocardial infarction
2. atherosclerosis
3. a third degree AV node block
4. mitral stenosis

Lymph does not contain:

The lymph eventually enters the circulation by draining into two specific ___________.
1. arteries
2. arterioles
3. capillaries
4. veins

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