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A potted plant was kept in the dark for 48 hours. Two leaves X and Y were treated as shown in the diagram below.

A potted plant was kept in the dark for 48 hours. Two leaves X and Y were treated as shown in the diagram below.
Biology4120171241.jpg
The experimental set-up was kept in sun light for six hours after which a starch test was carried out on the two leaves
a) What were the results of the starch test on leaves X and Y?
b) Give reasons for your answers in (a) above

Answers


John
a) X - Iodine solution turned blue hence presence of starch

Y - Iodine solution retains its yellow brown colour hence absence of starch

b) X - Acts as a control, where all requirements are present.

Y - Carbon (IV) oxide is absent. It is absorbed by potassium hydtoxide pellets, hence the rate of photosynthesis could take place.
johnmulu answered the question on May 1, 2017 at 09:47

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