Question

For the following multiple choice question, identify what you believe to be the correct answer. Then, in one to three sentences, concisely explain why you believe that your chosen answer is the correct one (as opposed to the other answer choices).

Which of the following types of capillary exchange would be most likely to occur in sinusoid capillaries if the solute were a large, hydrophilic molecule?

A. diffusion through cells

B. diffusion between cells or through holes in cells

C. transcytosis

D. A and B would be equally likely

E. A, B and C would be equally likely

Answer 1

Sinusoid capillaries also called discontinuous capillary and there is capillaries are usually found in liver, spleen, and bone marrow. These are “leakiest capillary characterized by incomplete basement membrane, possess large intercellular clefts, larger hole in their capillary wall in addition to small pores. Hence it allows the exchange of even large molecule

Answer is B. diffusion between cells or through holes in cells

Since wall of capillaries are made of lipid layers only lipophilic solute can diffuse through the cell. Hydrophilic substances ( polar substances) has to penetrate through intercellular gap or hole in the cell. Transcytosis is a vesicular transport for larger molecule since, sinusoid capillaries contain large holes in the cell transcytosis does not require in this capillary