With parallel flow, diffusion of urea happened at regions I and II but not at regions III, IV, or V because... A
Urea was too big to fit through the pores in regions III, IV, or V.
B
There was no concentration gradient for urea in regions III, IV, or V.
С
There was no urea in the blood in regions III, IV, and V.
D
The pore size was too small in regions III, IV, and V.

The correct answer is

b

Explanation:

First we can elimenate A and D because the pore size is the same.

C is wrong, there is still some urea in the blood, however is less

We are left with B which is the correct answer, i did the gizmo

in situ hybridization has been widely used for research applications, including clinical cytogenetics, gene mapping, tumor biology and studies of chromosome evolution.

here's your

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