Blood is a viscous fluid, so the heart must:

  1. only pump it once
  2. do no work
  3. do work to keep it flowing through the vessels
  4. make it compressible
Answer

C) do work to keep it flowing through the vessels

Energy is lost to viscous drag. SLO P-11-B-41 · Understanding

Physics MCQ · More Fluid Statics and Dynamics MCQs · Practise