Pieces of leaf epidermis were peeled from the plant Commelina communis - VCE - SSCE Biology - Question 6 - 2005 - Paper 1
Question 6
Pieces of leaf epidermis were peeled from the plant Commelina communis. The pieces were then placed in a solution of a dye that binds to potassium ions. You would ex... show full transcript
Worked Solution & Example Answer:Pieces of leaf epidermis were peeled from the plant Commelina communis - VCE - SSCE Biology - Question 6 - 2005 - Paper 1
Step 1
A. guard cells when the stomata are open.
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Answer
When the stomata are open, guard cells actively regulate the uptake of potassium ions, which helps in opening the stomatal pores. Given that the dye binds to potassium ions, it is expected that during this process, there will be a higher concentration of the dye in the guard cells.
Step 2
B. stomatal pore when the stomata are closed.
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Answer
When the stomatal pores are closed, the guard cells are flaccid, and there is not an active uptake of potassium ions. Therefore, the concentration of the dye would be lower in the stomatal pores at this time.
Step 3
C. epidermal cells when the stomata are open.
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Answer
Epidermal cells generally do not actively uptake potassium ions in the same manner as guard cells. Therefore, they are less likely to show a high concentration of the dye when the stomata are open.
Step 4
D. intercellular spaces of the leaf when the stomata are closed.
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Answer
When the stomata are closed, there would not be significant movement of potassium ions into the intercellular spaces, thus resulting in a lower concentration of the dye in those areas.
