Tutor profile: Gabriela F.
Subject: Food Science
What is the mechanism of action of an antioxidant?
They are radical scavengers since they can donate a proton (H+) to neutralize a free radical. This mechanism slows down oxidation reactions taking place inside a living organism or some foods.
Subject: Basic Chemistry
Why in some cases the hydrogen is put in the middle of the periodic table?
Even though the hydrogen has one electron in its only shell and normally it is located in the first group of the periodic table, the truth is it does not share any chemical properties with said group, so sometimes is put in the middle of the periodic table to symbolize it does not belong to any group fully.
How is the starch distributed in a variegated leaf?
Since photosynthesis takes place in the chloroplasts (that contain the chlorophyll green pigment), this is the place where glucose will be produced and then will be converted into starch for storage. So starch in a leaf will only be found in the green areas. The white areas of the variegated leaf do not have chloroplasts so they do not contain starch. This can be verified with the iodine test for starch.
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