Learnt osmosis at school but have always wondered...?

Question

I understand how osmosis work, but how do organisms store useful sugars without upsetting th osmotic balance? Does anyone have any ideas? Thanks

Answer 1

Well, they do upset the osmitic balance, and theoretically the sugars could just diffuse right back out of the cell equalizing the concentration gradient.

However, there is a neat trick to solve that problem, taking advantage of the characteristics of the lipid bilayer surrounding the cell. The carbohydrates are phosphorylated upon transport into the cell, the polar phosphate group cannot passively diffuse through the membrane, so the bacteria are able to accumulate sugars and "combat" diffusion by locking them into the cell.

Answer 2

Shiara_blade is right. Sugars are quickly used up in a cellular respiration process called glycolysis. In the process, glucose is converted to two different molecules, one of which is glyceraldehyde 3-phosphate. That molecule is converted by a bunch of other reactions, and oxidized, producing molecules called pyruvate. That molecule goes into Kreb's Cycle, and is used to release ATP for energy.

Answer 3

Sugars can be stored as non-soluble chains, for example starch, made from alpha glucose molecules only. These non-soluble chains therefore have no effect whatsoever on osmosis as they're no longer in solution.

Answer 4

The tendency here would be for water to enter the cell. A healthy living cell, however, has the ability to keep out excess water by "active transport". This process requires the cell to expend energy, which is generated by ATP. A dead cell will not have this ability, and would probably swell or burst.

Answer 5

They can store them as inactive complex carbohydrate molecules like starch and glycogen. It's also possible to actively regulate your osmotic balance, but that requires energy.

Answer 6

sugars get used rather quickly and aren't stored in the body. read up on glycolsis.