Question

As with Part H. you have a total body concentration of 300 mOsM and body volume of 3 liters. You now add 2 liters of a 500 mOsM solution. The solution is equal parts NaCI (nonpenetrating) and urea (penetrating), so it has 250 mosmol/L NaCI and 250 mosmol/L urea. Answer the following questions about your new solution:

Drag the terms on the left to the appropriate blanks on the right to complete the sentences.
The solution is_______ osmotic to the body.
What is the concentration of nonpenetrating solutes (NP) in the solution?
What is the internal concentration of the body's cells? (All intracellular solutes are nonpenetrating.)
When the cells reach equilibrium after addition of the solution to the body, has cell volume increased, decreased, or stayed the same?
Based on your answer regarding water movement, the solution was ____ tonic to the body's cells.
increased
hyper
300 mosmol/L
Stayed the same
300 mosmol/L
Hypo
lso
decreased
stayed the same

Answer 1

The added solution is hypertonic to the body, has 250 mosmol/L of nonpenetrating NaCl, and leads to a decrease in cell volume because it is hypertonic relative to the body cells' internal concentration of 300 mosmol/L.

Step-by-step explanation:

The solution is hypertonic osmotic to the body because the solution added has a higher total concentration of solutes (500 mOsM) than the body's original concentration (300 mOsM). The concentration of nonpenetrating solutes (NP) in the solution is 250 mosmol/L of NaCl. The internal concentration of the body's cells is 300 mosmol/L (all intracellular solutes are nonpenetrating), which is the approximate osmolarity of body fluids. When cells reach equilibrium after the addition of the solution, cell volume has decreased, due to water moving out of the cells to balance the higher osmolarity of the extracellular fluid. Based on the answer regarding water movement, the solution was hypertonic to the body's cells.

Answer 2

- The solution is hyperosmotic to the body.

- What is the concentration of nonpenetrating solutes (NP) in the solution? 500 mosmol/L

- What is the internal concentration of the body's cells? (All intracellular solutes are nonpenetrating.) 300 mosmol/L

- When the cells reach equilibrium after addition of the solution to the body, has cell volume increased, decreased, or stayed the same? increased

- Based on your answer regarding water movement, the solution was hypotonic to the body's cells.

Step-by-step explanation:

A hyperosmotic (or hypertonic) solution is a solution with a greater solute concentration. If a cell is placed in a hyperosmotic solution the water will leave the cell and the cell will shrink. Conversely, a hypotonic solution is a solution that has a lower concentration of solute. If a cell is placed in a hypotonic solution the water will enter the cell through osmosis and the cell increases in size. In this case, the NaCl is a non-penetrating solute, and thereby the concentration in the body's cells maintains constant. Moreover, urea is a penetrating solute, thereby it will penetrate in the cells until the equilibrium is reached (i.e., the cells will increase in volume).