starch, cellulose and glycogen⭐️

Question 1

What are the two forms of starch?

Answer 1

Amylose and amylopectin

Question 2

Discuss the structure of amylose

Answer 2

Long unbranched chains, angles of glycosidic bonds give it a coiled structure so it can be compact, good for storage. Forms an alpha helix

Question 3

Discuss the structure of amylopectin

Answer 3

Long branched chain, side branches allow enzymes to hydrolyse the glycosidic bonds easily so glucose can be released quickly

Question 4

Why is starch good for storage

Answer 4

Insoluble in water so doesn’t affect water potential, doesn’t cause water to enter the cells by osmosis so cells don’t swell. Large so does not move out of cells

Question 5

Discuss the structure of glycogen

Answer 5

Long branched chains. Loads of side branches to increase surface area so that stored glucose can be released quickly when hydrolysed. It’s compact so good for storage

Question 6

Discuss the structure of cellulose

Answer 6

Long unbranched chains linked together by hydrogen bonds to form strong fibres called microfibrils which make it strong and provides structural support for cells, such as cell wall. Each adjacent beta glucose is rotated 180 degrees.

Question 7

What is starch made out of

Answer 7

Alpha glucose

Question 8

What is glycogen made out of

Answer 8

Alpha glucose

Question 9

What is cellulose made out of

Answer 9

Beta glucose

Question 10

Why is glycogen a good store of glucose?

Answer 10

Insoluble so doesn’t move out of cells and doesn’t affect osmosis, highly branched, compact