The filament of spirogyra were put into equal volumes of sugar solutions X and Y. After 5 minutes, filaments from solution X had their cells contents rounded up while those from Y were unaffected. The experiment shows that
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Correct Answer: Option A
Explanation:
The correct answer is A: solution X was stronger than Y.
Explanation:
In this experiment, the observation that the cells from solution X had their contents "rounded up" while those from solution Y were unaffected suggests that solution X was a hypertonic solution relative to the contents of the Spirogyra cells. A hypertonic solution has a higher concentration of solutes (in this case, sugar) compared to the inside of the cells. As a result, water would move out of the cells by osmosis, causing the cell contents to shrink and round up.
On the other hand, solution Y had no effect on the cells, which implies that it was either isotonic (having the same concentration of solutes as the inside of the cells) or hypotonic (having a lower concentration of solutes than the cells). In both cases, there would be no net movement of water out of the cells, so they would remain unaffected.
Here’s why the other options are incorrect:
- B. Solution Y was stronger than X: This would not explain why solution X caused the cells to round up but solution Y did not. If Y were stronger, it should have caused a similar effect.
- C. Spirogyra used up the sugar in solution X: The rounding up of the cell contents is a physical process due to osmosis and not a result of Spirogyra metabolizing the sugar.
- D. Solution X is good for stimulating sexual reproduction in Spirogyra: The rounding up of the cells due to a hypertonic solution is not related to stimulating reproduction, which typically requires different conditions.
- E. Solution Y was less contaminated than X: Contamination would likely affect the overall effectiveness of the solution, but the difference observed is more likely due to the concentration of the sugar solution.
Thus, solution X was stronger (more concentrated) than solution Y, causing the cells to shrink due to water loss via osmosis.
The correct answer is A: solution X was stronger than Y.
Explanation:
In this experiment, the observation that the cells from solution X had their contents "rounded up" while those from solution Y were unaffected suggests that solution X was a hypertonic solution relative to the contents of the Spirogyra cells. A hypertonic solution has a higher concentration of solutes (in this case, sugar) compared to the inside of the cells. As a result, water would move out of the cells by osmosis, causing the cell contents to shrink and round up.
On the other hand, solution Y had no effect on the cells, which implies that it was either isotonic (having the same concentration of solutes as the inside of the cells) or hypotonic (having a lower concentration of solutes than the cells). In both cases, there would be no net movement of water out of the cells, so they would remain unaffected.
Here’s why the other options are incorrect:
- B. Solution Y was stronger than X: This would not explain why solution X caused the cells to round up but solution Y did not. If Y were stronger, it should have caused a similar effect.
- C. Spirogyra used up the sugar in solution X: The rounding up of the cell contents is a physical process due to osmosis and not a result of Spirogyra metabolizing the sugar.
- D. Solution X is good for stimulating sexual reproduction in Spirogyra: The rounding up of the cells due to a hypertonic solution is not related to stimulating reproduction, which typically requires different conditions.
- E. Solution Y was less contaminated than X: Contamination would likely affect the overall effectiveness of the solution, but the difference observed is more likely due to the concentration of the sugar solution.
Thus, solution X was stronger (more concentrated) than solution Y, causing the cells to shrink due to water loss via osmosis.