2.2 Carbohydrates and monosaccharides

Question 1

Carbohydrates are..

Answer 1

Carbon molecules + water

Question 2

Do carbons readily or not readily form bonds with other carbon atoms?

Answer 2

Readily. This allows a sequence of carbon molecules to be built up.

Question 3

Carbon containing molecules are known as what molecules?

Answer 3

Organic molecules,.

Question 4

Individual molecules that make up a chain are known as?

Answer 4

Monomers (mono - one)

Question 5

Longer chains of repeating monomer units are called?

Answer 5

Polymers (poly - many)

Question 6

Carbohydrates and proteins are often what?

Answer 6

Polymers.

Question 7

Four main elements?

Answer 7

Carbon, hydrogen, oxygen and nitrogen.

Question 8

A single and a pair of basic carbohydrate monomers (saccharides) are called what?

Answer 8

Monosaccharide, and disaccharide. Monosaccharides combined in much larger numbers are also called polysaccharides.

Question 9

The best known monosaccharide is glucose. What is the formula for glucose?

Answer 9

C6 H12 O6

Question 10

All monosaccharides and some disaccharides are reducing sugars. What is the test for this?

Answer 10

Benedicts test. Benedicts is an alkaline solution of copper(ii) sulfate. When a reducing sugar is heated with this, an insoluble red precipitate of copper(i) oxide forms.

Question 11

What are the steps to carry out benedicts test?

Answer 11

-Add 2cm of food sample to test tube (grind up with water if not already in liquid form). -Add equal ammount of benedicts. -heat mixture in bath for 5 mins.

Question 12

Resuts for benedicts test?

Answer 12

-no colour change = no reducing sugar. -green = very low concentration of reducing sugar. -yellow = low concentration of reducing sugar. -orange = medium concentration of reducing sugar. -red = high concentration of reducing sugar.

Question 13

a-glucose structure.