Cellulose, Starch, Reducing and Non-reducing sugars Flashcards Preview

Biological Molecules > Cellulose, Starch, Reducing and Non-reducing sugars > Flashcards

Flashcards in Cellulose, Starch, Reducing and Non-reducing sugars Deck (11):
1

Starch:

Made out of alpha glucose monosaccharides, and is a coiled, condensed, polysaccharide.
It has glycosidic bonds.

2

Why is it coiled?

The coils allow for larger quantities of starch to be stored.

3

Starch, aka.....?

Starch coil

4

Cellulose:

Made out of beta glucose monosaccharides, and every other monosaccharide is rotated 180 degrees to form a straight line.

5

Cellulose, aka......?

Beta pleated sheet

6

Which disaccharides are reducing sugars?

Maltose and Lactose

7

What is a reducing sugar?

Donates electrons which are used to reduce Cu2+ (blue) to Cu+ (red).
>=>0>=>0
(0 = electron)

8

What test can you use to find a reducing sugar?
Give a description.

Benedicts reagent test.
When you heat benedicts reagant with a reducing sugar the Cu2+ will change to Cu+. Copper Oxide is formed, and a red precipitate.

9

Which disaccharides are non-reducing sugars?

Sucrose.

10

What is a non-reducing sugar?

It is a sugar with no free electrons.
>=>0<=<
(0 = electron)

11

What test can you use to find a non-reducing sugar?
Give a description.

Test with benedicts reagent - no precipitate formed.
Apply dilute hydrochloric acid to a new sample to separate the molecules.
Then neutralise the solution with NaHCO3.
Retest solution with benedicts reagent, a red precipitate will form.