AQA A LEVEL BIOLOGY REVISION NOTES 2021/2022
AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
CONTENTS
1.1.1 Biological Molecules: Key Terms
1.1.2 Biological Molecules: Reactions
1.1.3 Monosaccharides
1.1.4 Glucose
1.1.5 The Glycosidic Bond
1.1.6 Chromatography: Monosaccharides
1.1.7 Disaccharides
1.1.8 Starch & Glycogen
1.1.9 Cellulose
1.1.10 Biochemical Tests: Sugars & Starch
1.1.11 Finding the Concentration of Glucose
1.1.1 BIOLOGICAL MOLECULES: KEY TERMS
Biological Molecules: Key Terms
There is much variety of life within and between organisms but the biochemical basis of life is
similar for all living things
The key molecules that are required to build structures that enable organisms to function
are:
Carbohydrates
Proteins
Lipids
Nucleic Acids
Water
Monomers are the smaller units from which larger molecules are made
Polymers are molecules made from a large number of monomers joined together in a chain
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AQA A Level Biology Resources Page 1
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
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YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 2
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
, AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
The key biological molecules for living organisms
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REVISION NOTES TOPIC QUESTIONS PAST PAPERS
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YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
Carbohydrates, proteins, lipids and nucleic acids contain the elements carbon (C) and
hydrogen (H) making them organic compounds
Carbon atoms are key to the organic compounds because:
Each carbon atom can form four covalent bonds – this makes the compounds very
stable (as covalent bonds are so strong they require a large input of energy to break
them)
Carbon atoms can form covalent bonds with oxygen, nitrogen and sulfur
Carbon atoms can bond to form straight chains, branched chains or rings
Carbon compounds can form small single subunits (monomers) that bond with many
repeating subunits to form large molecules (polymers) by a process called polymerisation
Macromolecules are very large molecules
That contain 1000 or more atoms therefore having a high molecular mass
Polymers can be macromolecules, however not all macromolecules are polymers as
the subunits of polymers have to be the same repeating units
Carbohydrates
Carbohydrates are one of the main carbon-based compounds in living organisms
All molecules in this group contain C, H and O
As H and O atoms are always present in the ratio of 2:1 (eg. water H2O, which is where
‘hydrate’ comes from) they can be represented by the formula Cx (H2O)y
The three types of carbohydrates are monosaccharides, disaccharides and
polysaccharides
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 4
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
CONTENTS
1.1.1 Biological Molecules: Key Terms
1.1.2 Biological Molecules: Reactions
1.1.3 Monosaccharides
1.1.4 Glucose
1.1.5 The Glycosidic Bond
1.1.6 Chromatography: Monosaccharides
1.1.7 Disaccharides
1.1.8 Starch & Glycogen
1.1.9 Cellulose
1.1.10 Biochemical Tests: Sugars & Starch
1.1.11 Finding the Concentration of Glucose
1.1.1 BIOLOGICAL MOLECULES: KEY TERMS
Biological Molecules: Key Terms
There is much variety of life within and between organisms but the biochemical basis of life is
similar for all living things
The key molecules that are required to build structures that enable organisms to function
are:
Carbohydrates
Proteins
Lipids
Nucleic Acids
Water
Monomers are the smaller units from which larger molecules are made
Polymers are molecules made from a large number of monomers joined together in a chain
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 1
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
, AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 2
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
, AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
The key biological molecules for living organisms
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 3
REVISION NOTES TOPIC QUESTIONS PAST PAPERS
, AQA A Level Biology Revision Notes savemyexams.co.uk
YOUR NOTES
1.1 Biological Molecules: Carbohydrates ⬇
Carbohydrates, proteins, lipids and nucleic acids contain the elements carbon (C) and
hydrogen (H) making them organic compounds
Carbon atoms are key to the organic compounds because:
Each carbon atom can form four covalent bonds – this makes the compounds very
stable (as covalent bonds are so strong they require a large input of energy to break
them)
Carbon atoms can form covalent bonds with oxygen, nitrogen and sulfur
Carbon atoms can bond to form straight chains, branched chains or rings
Carbon compounds can form small single subunits (monomers) that bond with many
repeating subunits to form large molecules (polymers) by a process called polymerisation
Macromolecules are very large molecules
That contain 1000 or more atoms therefore having a high molecular mass
Polymers can be macromolecules, however not all macromolecules are polymers as
the subunits of polymers have to be the same repeating units
Carbohydrates
Carbohydrates are one of the main carbon-based compounds in living organisms
All molecules in this group contain C, H and O
As H and O atoms are always present in the ratio of 2:1 (eg. water H2O, which is where
‘hydrate’ comes from) they can be represented by the formula Cx (H2O)y
The three types of carbohydrates are monosaccharides, disaccharides and
polysaccharides
© 2015-2021 Save My Exams Ltd
AQA A Level Biology Resources Page 4
REVISION NOTES TOPIC QUESTIONS PAST PAPERS