A student put some drops of Lugols iodine solution into the water in the beaker shown above. The water turned red. After a short time, the starch solution inside the dialysis tubing turned black. Which function of the cell membrane was the student demonstrating?

TRANSPORT INTO AND OUT OF THE CELL

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Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

A student put some drops of Lugol’s iodine solution into the water in the beaker shown above. The water turned red. After a short time, the starch solution inside the dialysis tubing turned black. Which function of the cell membrane was the student demonstrating?

A	Facilitated diffusion of starch
B	active transport of hydrogen ions
C	diffusion through a permeable membrane
D	diffusion through a semipermeable membrane.

Explanation:

Detailed explanation-1: -Many different food groups contain a carbohydrate known as starch. Using an iodine solution, you can test for the presence of starch. When starch is present, the iodine changes from brown to blue-black or purple.

Detailed explanation-2: -Lugol’s solution is made of iodine, potassium iodide, and water. It turns a dark blue or black color when it reacts with starch.

Detailed explanation-3: -On adding the iodine solution to starch, the two react to produce a blue-black color. Q. Rice is a rich source of starch and iodine gives blue black colour with starch.

Detailed explanation-4: -Amylose in starch is responsible for the formation of a deep blue color in the presence of iodine. The iodine molecule slips inside of the amylose coil.

There is 1 question to complete.