# From the stomach into the arterial circulation

• Test Prep
• 15
• 100% (31) 31 out of 31 people found this document helpful

This preview shows page 9 - 13 out of 15 pages.

from the stomach into the arterial circulation, determine the new arterial and venousconditions if Q and±pare constant. How do you think the body will change due tosystemic regulation?Name: _______________________________________9
5. Pulmonary capillary perfusion (25 points).In class and problem set 3 we determined how oxygen and carbon dioxideconcentration varies in the pulmonary capillary system as a function of axial position z. We willnow focus on oxygen transport for this problem.A.(4 points) Draw a diagram for this problem. Be sure to label the control volume, relevantoxygen concentrations, and transport rates. Now write the expression describing thepartial pressure of oxygen as a function of z, or Pc,O2(z). You may simply write theequation from your notes, or re-derive if necessary.B.(2 points) Under conditions in which PA,O2= 105 mm Hg, Pa,O2= 44 mm Hg, and Pv,O2=100 mm Hg, is oxygen diffusion or blood perfusion greater?C.(2 points) If blood flow rate (Qp) doubled while the alveolar and arterial oxygenconcentrations remained constant, calculate the new venous oxygen concentration(Pv,O2) after the system attained a new steady state.D.(6 points) To determine how the system in part C would approach the new steady state,we would have to conduct a new mass balance in which the accumulation term is non-zero. Set-up this mass balance, simplify using the diffusing capacity relationship, anddetermine a partial differential equation with Pc,O2varying in both time and space.Assume volume is constant.E.(8 points) Since we cannot solve the equation in part D, let’s now make the assumptionthat the capillary is well-mixed. Draw and label a new diagram, and perform the time-varying mass balance. Again use the diffusing capacity relationship and assume volumeis constant.F.(3 points) Integrate the differential equation in part E and solve for t using the Pv,O2determined in part B as the initial condition, Pv,O2in part C as the final condition, PA,O2and Pa,O2values given in part B, and the following values:DL= 30 mL O2/min·mm HgQp= 10 L/minβb= 0.002 mL O2/mL·mm HgVc= 0.5 LName: _______________________________________12

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 15 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Fall
Professor
staff
Tags
• • • 