Question

1. Dr. Levesque removed de-shelled eggs from an isotonic solution and placed them in each of the following solutions: 1 egg in pure water, 1 egg in 10% sucrose, 1 egg in 20% sucrose, and 1 egg in 40% sucrose. The cell membrane is not permeable to sucrose and the isotonic solution is 20% sucrose. After time has passed she will weigh them. Which egg will weigh the most? The least? Which eggs will gain weight relative to their starting weight? Which eggs will lose weight?

Answer 1

We have given that concentration of isotonic solution is 20%. It means that the concentration of solution in the egg is also 20%. Also it is given that the de-shelled eggs are placed in different solutions.

The egg which is places in pure water will weigh highest because the pure water is hypotonic with respect to the egg. So water will move inside the egg and thus increase its weight.

The egg which is placed in 40% sucrose solution will weigh the least because the sucrose solution is hypertonic with respect to the egg. So water will move out from the egg and thus the weight will decrease.

The eggs placed in pure water and 10% sucrose solution will gain weight relative to their starting weight because these are hypotonic with respect to the eggs and thus water will move inside the eggs and increase their weight.

The eggs placed in 40% sucrose will lose weight because the solution is hypertonic with respect to the eggs and thus water will move out of the eggs and decrease their weight.