1. Your goal is to make an isotonic intravenous solution for an emergency room patient who
has lost a lot of blood. The available solutes include glucose (300 mM), NaCl (150 mM), and
urea (300 mM). What solutes should she use to make up the IV solution with an osmolarity
of 300 mOsm (isosmotic), making sure that it will also be isotonic?
Explain your answer.
Assume that the cell is permeable to urea, glucose, but not to NaCl and that the osmolarity of
the cell is 300 mOsm.
2. If a 10% sucrose solution is separated from a 20% sucrose solution by a membrane
impermeable to sucrose, in which direction will net movement of water occur?
A) from the 10% sucrose solution to the 20% sucrose solution only
B) from the 20% sucrose solution to the 10% sucrose solution only
C) There will be no net movement of water in this case.
D) None of the answers are correct.
1. Your goal is to make an isotonic intravenous solution for an emergency room patient who
has lost a lot of blood. The available solutes include glucose (300 mM), NaCl (150 mM), and
urea (300 mM). What solutes should she use to make up the IV solution with an osmolarity
of 300 mOsm (isosmotic), making sure that it will also be isotonic?
Explain your answer.
Assume that the cell is permeable to urea, glucose, but not to NaCl and that the osmolarity of
the cell is 300 mOsm.
2. If a 10% sucrose solution is separated from a 20% sucrose solution by a membrane
impermeable to sucrose, in which direction will net movement of water occur?
A) from the 10% sucrose solution to the 20% sucrose solution only
B) from the 20% sucrose solution to the 10% sucrose solution only
C) There will be no net movement of water in this case.
D) None of the answers are correct.
