Beetroot cells contain a family of dark red pigments called betalains. The selectively permeable nature of the beetroot cells keeps the internal environment of the cell separate from the external environment of the cell. Researchers are interested in determining whether the selective permeability of beetroot cells is due to the cell membrane or if it is due to the cell wall.

Exposure to cellulase is known to damage the structure of the cell wall. An experiment is set up in which beetroot cells are placed in an aqueous solution with cellulase and in one without cellulase.

Which of the following results best refutes the alternative hypothesis that selective permeability is a consequence of the cell wall?

A
When beetroot cells are placed in a solution with cellulase, the solution turns dark red.

B
When beetroot cells are placed in a solution with cellulase, the solution remains clear.

C
When beetroot cells are placed in a solution, it turns dark red with or without cellulase present.

D
Since plant cells contain cell membranes, not cell walls, the alternate hypothesis cannot be tested.

The results which best refutes the alternative hypothesis that selective permeability is a consequence of the cell wall is:

A cell wall are those parts of a cell that holds the cell together and it has a definite structure.

Furthermore, a cell membrane is not affected by the process of cellulose digestion, but this process hurts the cell wall structure and damages it.

As a result of this, when a beetroot cell is put in a solution that contains cellulase, the solution does not remain clear because selective permeability is a consequence of the cell wall.

Therefore, the correct answer is option B

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B. When beetroot cells are placed in a solution with cellulase, the solution remains clear.

Explanation:

Cell membrane are not destroyed or damaged as cellulase digests cellulose, rather it damages the structure of the cell wall.

In conclusion, even though the Beetroot cell wall has been damaged, the lack of change in the color of the solution suggests that the betalain is not leaking out thereby refuting the claim that the alternative hypothesis that selective permeability is a consequence of the cell wall.