Carbohydrates - Monosaccharides - 1.2 Flashcards Preview

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Flashcards in Carbohydrates - Monosaccharides - 1.2 Deck (22)
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1
Q

What are carbohydrates?

A

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

2
Q

What are carbon-containing molecules known as?

A

Organic molecules

3
Q

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

A

Organisms being based on the versatile carbon atom.

4
Q

What is a monomer?

A

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

5
Q

What are some examples of monomers?

A
  • Monosaccharides
  • Amino Acids
  • Nucleotides
6
Q

What are polymers?

A

Molecules made from many monomers joined together.

7
Q

What are some examples of polymers?

A
  • Carbohydrates

- Proteins

8
Q

What are the four elements that make up most polymers?

A
  • Carbon
  • Hydrogen
  • Oxygen
  • Nitrogen
9
Q

What is the basic carbohydrate monomer?

A

A sugar known as a saccharide.

10
Q

What is a single carbohydrate monomer called?

A

Monosaccharide

11
Q

What is a pair of carbohydrate monomers called?

A

Disaccharide

12
Q

What are many carbohydrate monomers called?

A

Polysaccharides

13
Q

What are monosaccharides?

A

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

14
Q

What are example of monosaccharides?

A
  • Glucose
  • Galactose
  • Fructose
15
Q

What are the two isomers of glucose?

A
  • Alpha-glucose

- Beta-glucose

16
Q

What are reducing sugars?

A

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

17
Q

What is reduction?

A

A chemical reaction involving the gain of electrons or hydrogen.

18
Q

What is a reducing sugar?

A

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

19
Q

What is the test for reducing sugars?

A

The Benedict’s test

20
Q

What is Benedict’s reagent?

A

An alkaline solution of copper (II) sulphate.

21
Q

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

A

An insoluble red precipitate of copper (II) oxide

22
Q

What is the Benedict’s test for reducing sugar?

A
  • 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.