Biology- Lab 6 - Review Quiz: Osmosis & Diffusion, part 2

You made a wet mount slide of each blood/solution mixture when testing for tonicity. What did you learn from this? A. In the tube with the highest concentration of solutes, the cells had shriveled (crenated). B. The difference in tonicity did not affect the red blood cells at all. C. Both opaque tubes contained completely normal-looking blood cells. D. Temperature had a significant effect on the red blood cells. E. The red blood cells were too small to block light.

A. In the tube with the highest concentration of solutes, the cells had shriveled (crenated). Explanation: You must look under the microscope to see whether the RBCs shape has changed (normal, crenated or burst). The hypertonic solution (10% NaCl) showed crenated cells when looking under the microscope.

Select all that apply: Tonicity of a solution A. is related to solute content.is related to solute content. B. is related to the pH of the solution.is related to the pH of the solution. C. gives information about potential changes in cell volume when cells are placed in that solution. D. is closely related to the temperature of the solution.is closely related to the temperature of the solution. E. is related to membrane permeability to solutes.is related to membrane permeability to solutes.

A. is related to solute content.is related to solute content. C. gives information about potential changes in cell volume when cells are placed in that solution. E. is related to membrane permeability to solutes.is related to membrane permeability to solutes. Explanation: Tonicity is defined as the ability of a solution to change the volume of a cell through osmosis, which is the movement of water across a selectively permeable membrane from a hypotonic solution (low solute, high water) into a hypertonic solution (high solute, low water).

If blood cells are placed in a hypertonic solution, A. the cells will shrink due to water loss by the cell. B. the cells will be unaffected since they have a cell membrane to separate them from the solution. C. the cells will shrink due to the loss of solutes from the blood cell. D. the cells will swell due to diffusion. E. the cells will burst due to active transport.

A. the cells will shrink due to water loss by the cell. Explanation: A solution with a lower concentration of water and a higher concentration of solute in comparison to another solution it is called a hypertonic solution. If blood cells are placed into a hypertonic solution, the cell will lose water and shrink as the water moves down its concentration gradient from the cell into the solution.

Based on the Tonicity in Elodea Cells lab, a hypotonic environment causes a cell to swell or burst because Check All That Apply A. the water in the solution moves into the plant cell. B. the water in the solution moves out of the plant. C. the solutes in the solution have a higher concentration than the solute concentration inside the plant cell. D. the solutes in the solution have a lower concentration than the solute concentration inside the plant cell. E. the water is moving down its concentration gradient from high to low. F. the water is moving down its concentration gradient from low to high.

A. the water in the solution moves into the plant cell. D. the solutes in the solution have a lower concentration than the solute concentration inside the plant cell. E. the water is moving down its concentration gradient from high to low.. Explanation: The water moved across the selectively permeable membrane down its concentration gradient from an area of high water concentration to an area of low water concentration. There were fewer solutes in the solution and more solutes in the cell, which is why the water moved into the cell.

During a hurricane, salt water invades fresh water marshes causing many of the plants to die and ultimately the loss of soil. The plants are killed because the salt-water solution is ________ to the plants drawing water from the plant cells. A. oligotonic B. hypertonic C. mesotonic D. isotonic E. hypotonic

B. hypertonic explanation: The hypertonic 10% NaCl solution produced the shrunken Elodea cells and the hypotonic distilled water solution produced the swollen Elodea cells. So if you placed a fresh water plant into the hypertonic salt-water marsh environment the water should leave the fresh water plant causing death.

When testing tonicity of red blood cells, if the solution became transparent after adding blood cells, you could assume A. the solution was hypotonic and the cells had remained intact. B. the solution was hypotonic and the cells had burst. C. the solution was isotonic and the cells had burst. D. the solution was hypertonic and the cells had shrunk. E. the solution was hypertonic and the cells remained intact.

B. the solution was hypotonic and the cells had burst. Explanation: If the blood becomes transparent then the red blood cells (RBCs) are not blocking the light, so the RBCs must have been destroyed if the solution is transparent.

Why do you think it is a good idea to soak wilted lettuce in cool water before serving it? A. The water is a hypertonic solution relative to the cytoplasm in the plant cells, so the plant cells will gain water and the lettuce will become crisper. B. The water is an isotonic solution relative to the cytoplasm in the plant cells, so they will gain water and the lettuce will become less wilted. C. Soaking the lettuce in water would have no effect. D. The water is a hypotonic solution relative to the cytoplasm in the plant cells, so the plant cells will gain water and the lettuce will become crisper. E. The water is a hypotonic solution relative to the cytoplasm in the plant cells, so the plant cells will gain water and the lettuce will become more wilted.

D. The water is a hypotonic solution relative to the cytoplasm in the plant cells, so the plant cells will gain water and the lettuce will become crisper. Explanation: The hypertonic 10% NaCl solution produced the shrunken Elodea cells and the hypotonic distilled water solution produced the swollen Elodea cells. If you placed slightly wilted lettuce in a hypotonic water solution the water should enter the lettuce cells and cause the cells to swell.

After soaking for one hour in a solution of unknown concentration, a slice of potato appears to be very soft and limp. You can determine that the solution is A. isotonic. B. hypotonic. C. hypertonic. D. tonic. E. I cannot determine anything without comparing multiple solutions.

C. hypertonic.

When conducting the Tonicity of Red Blood Cells lab, if you had chosen the hypothesis, 'Red blood cells placed in an isotonic solution will draw the water out of the cells causing the cell volume to decrease', what would you have seen when you looked under the microscope at the cells? A. cells with irregular shapes B. normal cells C. cells bursting D. crenation

D. crenation Explanation: The hypertonic solution (10% NaCl) showed crenated cells when looking under the microscope because the water was leaving the red blood cells.

Tonicity in cells refers to the concentration of solute in a solution outside of a cell, relative to A. the swelling of the cell. B. the permeability of the cell membrane. C. the presence of a cell wall. D. the number of cell fragments inside the cell. E. the solute concentration of the cytoplasm inside the cell.

E. the solute concentration of the cytoplasm inside the cell. Explanation: Tonicity is defined as the ability of a solution to change the volume of a cell through osmosis, which is the movement of water across a selectively permeable membrane from a hypotonic solution (low solute, high water) into a hypertonic solution (high solute, low water).