The Student Room Group

difference and simmiliarities between amylopectin & glycogen plus another question...

ok so similarities amylopectin and glycogen both consist of a-1,4 and a-1,6 glycosidic bond...and they r both branched chain...are thereany more similrities?? and what about differences??

then i was just doin one of the past papers of unit 1...the june 2005 unit 1 paper and i cud not figure out an answer for question no 4 part b...where theres a diagram of 2 cells with different colored stained proteins on the cell surface membrane...n another diagram of a cell if the previous two cells were fused together...and the question was to explain wat we understand from the fused cell...if anyone remembers the answer or anyth plz plz plz let me ok? thnx...:smile:

Reply 1

Amylopectin and glycogen have a very similar structure; they are both made of alpha glucose molecules and have 1,4 and 1,6 glycosidic bonds. Glycogen has more branches than amylopectin though. I think that's about it in terms of their structure... in terms of their function, amylopectin is part of starch, which is a energy storage compound in plant cells. Glycogen is an energy storage compound in animal cells and found in liver & muscle cells.

As for the past paper question... Edexcel, correct? If I'm thinking of the same question as you, the diagram can be explained by the fact that the cell membrane is fluid; because it is fluid, the phospholipids can move, and so the proteins floating in the bilayer can move too. Thus when the two cell membranes fused together, the proteins could change their positions in the new cell membrane and demonstrate the mixing of colours as in the diagram.

HTH :smile: Do you have Unit 1 this Wednesday too?