Question

Trying to make sure I'm answering these questions correctly. I'm confused on question d. I can explain why in terms of concentration gradient and the fact it's in a hypotonice solution which would cause water to go into the blood vessel, but don't know how to answer it in terms of hydrostatic pressure.

6. Imagine blood in a vessel that has an osmolarity of 300 mEq (a measure of the concentration of particles). Now, imagine that the IF around the vessel has an osmolarity of 100 mEq.

a. Where are there more particles: inside or outside the vessel? ___________inside__________

b. Will water enter or leave the vessel because of its concentration gradient? _______enter___.

c. Since particles are always in motion, they bang against the walls of the blood vessel. The pressure resulting from that banging of particles against a barrier is called hydrostatic pressure. Is the hydrostatic pressure higher inside or outside the vessel? _______inside__________

Explain your reasoning. Because there are more particles inside the vessel there are more collisions, which means the hydrostatic pressure is higher inside.

d. In terms of hydrostatic pressure and ignoring the concentration gradient, is fluid drawn into or out of the vessel? _____________________________ Explain your reasoning.

Answer 1

Water have a tendency to move from low osmolarity to higher osmolarity , so water will go into the blood vessel. Since osmolarity corresponds to total concentration of all solutes in the solution and blood vessel have more osmolarity it has maximum number of solutes present .

A) blood vessel therfore have more particles inside

B) water therefore will enter the blood vessel

C) hydrostatic pressure is more in the blood vessel

Hydrostatic pressure is the pressure caused the weight of the blood above it in the vessel, it is the pressure exerted by the fluid at a given point due to weight of fluid above it .it also depends on the depth.

Capilary hydrostatic pressure is the force that drives fluid out of capillaries into the tissue , As the fluid excape into the tissue the hydrostatic pressure in the tissue also increases

Since the water level in the IF is more more force is required to send water form blood vessel to IF therefore Hydrostatic pressure is more in the blood vessel

D) water will move from IF into the blood vessel

Because hydrostatic pressure is less in the IF that is only less force is required to move water therfore water will move into the blood vessel

Putting it simply hydrostatic pressure is the water being pushed put of the blood vessel, if there is more water in the blood vessel it will get pushed out into the tissue and will cause edema ,

Since hydrostatic pressure is high in blood vessel and water content in the blood is less...so water will move from intestital fluid to blood