Carbohydrates - Monosaccharides - 1.2

Question 1

What are carbohydrates?

Answer 1

Carbon molecules (carbo) combined with water (hydrate).

Question 2

What are carbon-containing molecules known as?

Answer 2

Organic molecules

Question 3

What is the variety of life that lives on earth a consequence of?

Answer 3

Organisms being based on the versatile carbon atom.

Question 4

What is a monomer?

Answer 4

One of many small molecules that combine to form larger ones known as polymers.

Question 5

What are some examples of monomers?

Answer 5

• Monosaccharides
• Amino Acids
• Nucleotides

Question 6

What are polymers?

Answer 6

Molecules made from many monomers joined together.

Question 7

What are some examples of polymers?

Answer 7

• Carbohydrates

- Proteins

Question 8

What are the four elements that make up most polymers?

Answer 8

• Carbon
• Hydrogen
• Oxygen
• Nitrogen

Question 9

What is the basic carbohydrate monomer?

Answer 9

A sugar known as a saccharide.

Question 10

What is a single carbohydrate monomer called?

Answer 10

Monosaccharide

Question 11

What is a pair of carbohydrate monomers called?

Answer 11

Disaccharide

Question 12

What are many carbohydrate monomers called?

Answer 12

Polysaccharides

Question 13

What are monosaccharides?

Answer 13

Sweet-tasting, soluble substances that have the general formula (CH20)n, where n can be any number from three to seven.

Question 14

What are example of monosaccharides?

Answer 14

• Glucose
• Galactose
• Fructose

Question 15

What are the two isomers of glucose?

Answer 15

• Alpha-glucose

- Beta-glucose

Question 16

What are reducing sugars?

Answer 16

All monosaccharides and some disaccharides (e.g. maltose) are reducing sugars.

Question 17

What is reduction?

Answer 17

A chemical reaction involving the gain of electrons or hydrogen.

Question 18

What is a reducing sugar?

Answer 18

A sugar that can donate electrons to (or reduce) another chemical.

Question 19

What is the test for reducing sugars?

Answer 19

The Benedict’s test

Question 20

What is Benedict’s reagent?

Answer 20

An alkaline solution of copper (II) sulphate.

Question 21

What happens when a reducing sugar is heated with Benedict’s reagent?

Answer 21

An insoluble red precipitate of copper (II) oxide

Question 22

What is the Benedict’s test for reducing sugar?

Answer 22

• Add 2cm3 of the food sample to be tested to a test tube. If the sample is not already in liquid form, first grind it up in water.
• Add an equal volume of Benedict’s reagent.
• Heat the mixture in a gently boiling water bath for five minutes.
• If reducing sugar is present, solution turns orange-brown.