how does the structural features of glycogen relate to its function?

Question 1

what is the significance of glycogen being a large molecule made up of many alpha-glucose residues, & how does it contribute to its function?

Answer 1

• as glycogen is a large molecule, it is insoluble in water & thus prevented from diffusing out of cells
• plus, glycogen can also be stored in large amounts without having any great effect on water potential of cells, allowing it to act as a storage carbohydrate in most vertebrate animals

Question 2

what is the significance of glycogen having a compact shape, & how does it contribute to its function?

Answer 2

• as glycogen folds into a compact shape, it allows large amounts of glucose to be stored within the fixed volume of the liver & muscle cells,
• thus, allowing glycogen to carry out its function of being a storage carbohydrate in most vertebrate animals

Question 3

what is the significance of glucose having a highly branched structure, & how does it contribute to the function of glycogen?

Answer 3

• due to glycogen’s highly branched structure, there will be many free ends for enzymes to bind & hydrolyse glycogen
• thus, more glucose can be released at a faster rate to drive ATP synthesis, allowing glycogen to function as an energy source for most vertebrate animals

Question 4

why is glycogen more suitable than amylopectin as a storage carbohydrate in vertebrate animals?

Answer 4

• as glycogen has a higher number of branch points compared to amylopectin,
• there are more free ends in glycogen compared to amylopectin for enzymes to bind & for hydrolysis to occur, allowing more glucose to be released at a faster rate
• which is highly important, as animals are not stationary, unlike plants, & will need the glucose to be used to synthesis ATP for energy