Why is glucose transported across cell plasma membrane?

Answer 1

They are required for the effective means of the "Electron Transport Chain" to function. Without protein channels and carriers the body could not effectively move carbohydrates around the body. Glucose is the only "sugar/carbohydrate" that can pass freely through cell membranes. Fats, sugars and other carbohydrates need assistance to complete what is known as the "KREB CYCLE" turning carbohydrates into ATP (Adenosinetriphosphate) or in lamens terms "energy".

The simplest way to actually understand how it works is this: think of the whole Electron Transport Chain like a "FEDEX" company. You are a business of raw carbohydrates, fats etc and you need them refined and turned into another product in this case, Energy (ATP). So you pick up the phone and you call Fedex, they send a courier to pick it up (in this case it is the protein carrier) which takes it back to the DEPOT and places it onto a destination belt (your protein channel) where then it gets shipped off by other parts of FEDEX till it reaches its destination of the ETC(Electron transport chain) and finally produces ATP or energy.

It's not that difficult if you can imagine it this way and substitute your biological terminology for simpler occupations within a courier company. Without the carriers or the protein channels the body would absolutely have no way of breaking down the carbohydrates to turn them into ATP.

Answer 2

Because glucose is a polar molecule, and because the phosopholipid bylayer is hydrophobic it cannot passthrough, therefore protein channels with a hydrolytic lining are required to transport it in and out of the cell.

Answer 3

because in this case it is used the active transport