Regarding the physical characteristics of the circulation:

• A. arterioles have a strong muscular wall but can close completely
• B. the arterial system contains the greatest volume of blood at any given time
• C. the aorta has a greater total cross sectional area than the venae cavae
• D. velocity is directly proportional to the cross sectional area of the blood vessel
• E. Reynold s number represents a measure of laminar blood flow