why is starch a suitable form in which to stre food?

Question

potato cells

Answer 1

Glucose is one of the most common energy sources for living organisms. However it is a small molecule and if a cell needs lots of it, it would mean having lots of small molecules inside it, leading to an increased osmotic pressure. That would result in water molecules entering the cell and depending on the conditions this influx could continue until the cell bursts . Since osmotic pressure depends on the number of molecules but not their size, cells combine lots of small glucose molecules into fewer, big polymers (starch) and thus avoid the increase in osmotic pressure. Roughly you could imagine starch molecules as chains of glucose molecules which the cell elongates with additional glucose when there is plenty of it around or shorten in order to use glucose when it needs energy.

Answer 2

Glucose is stored as Glycogen in the liver by a process called Glycogenesis. To much glucose in cells would cause the cells to lyse, this would be fatal. So the body converts it to Glycogen to store for when it needs to be used.

Answer 3

cos it is energy rich food