Discuss the important factors in exchange of gases and substrates between capillaries and tissue cells. 

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College Answer

Good answers were based around Fick’s Law, Starling forces and the Gibb’s 
Donnan effect. 

It was expected that candidates would give Fick’s equation and describe the 
components : 
Fick’s Law J = -DA dc/dx

Candidates were also expected to describe Starlings equation and the equation for 
Osmotic Pressure. Starling Equation: 
Fluid movement = k[(Pc-Pi) – s(πp – πi)] 
Osmotic pressure : sRT(Ci-Co).

Gibb’s Donnan effect and, other mechanisms of transport (filtration and pinocytosis) 
was also expected for a good answer.

Syllabus: A combination C1c2.d, C21 2.e, C2b2.c, C2b2.e 
References: Pharmacology and Physiology in Anesthetic Practice, Stoelting pgs 
294-300, 322- 325