AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Describe how you would use a biochemical test to show that a
solution contained a non-reducing sugar, such as sucrose. [3]
,first reducing sugars test; boil with dilute HCl acid then
Neutralise with NaHCǑ, add benedict and heat to 95 degrees C
brick red ppt forms if reducing sugar is present
Describe a chemical test you could carry out to show that a
piece of coconut contains lipids. [3]
(Crush in) ethanol / alcohol; Add (to) water (Order of adding is
critical for this point); Emulsion / white colour
Explain what is meant by a polymer. [1]
Molecule) made up of many identical/similar
molecules/monomers/ subunits;
Name the reaction which occurs when starch is broken down
into maltose. [1]
Hydrolysis
What is the formula for lactose? [2]
C12 ; H22Ō1
,AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Describe how β-glucose molecule differs from a molecule of α-
glucose. [1]
H at top right end (instead of OH) / OH at bottom (carbon 1)
Show two ways in which the structure of cellulose is different
from the structure of starch. [2]
Starch 1,4 and 1,6 bonds / branching Cellulose 1,4 bonds / no
1,6 bonds / straight; starch All glucoses /monomers same way
up cellulose Alternate glucoses upside down; starch Helix /
coiled/compact cellulose Straight; Starch monomer Alpha
glucose Cellulose monomer Beta glucose
Describe the structure of starch and explain how its structure is
related to its function. [3]
Formed from α glucose; Joined by condensation/ by the
removal of a water molecule/ glycosidic bonds; Between
(carbons) 1 and 4 (and 1 and 6); Coiled chain; compact; (Allows)
storage of large amount in a small space; Insoluble so has no
effect on osmosis/water potential; Branches; (Allows) rapid
breakdown/release of glucose / hydrolysis;
,AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
The structure of a phospholipid molecule is different from that
of a triglyceride. Describe how. [2]
triglyceride has three fatty acids and phospholipid has two; no
phosphate group present in triglyceride but present in
phospholipid.
What is an unsaturated fatty acid? [1]
Some / two carbons with only one hydrogen / (double bonds)
between carbon atoms / not saturated with hydrogen;
Describe the structure of cellulose and explain how its structure
is related to its function. [3]
Alternate β-glucose rotated 180o, long straight chains, Many
hydrogen bonds join (polysaccharide) chains/molecules to each
other / makes microfibrils / gives tensile strength;
Which elements are found in proteins? [1]
Carbon, hydrogen, oxygen, nitrogen (sometimes sulphur)
Describe how you would use a biochemical test to show that a
solution contained protein. [2]
Biuret / alkali + copper sulphate; Lilac/purple/mauve/violet;
, AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Which bonds are found in a)Primary structure [1]b)Secondary
structure [1] c)Tertiary structure [2]
a)Peptide b) Hydrogen (and peptide) c)Ionic, disulphide bridges,
hydrophobic interactions (hydrogen and peptide)
Explain how a change in the primary structure of a globular
protein may result in a different three-dimensional structure.
[3]
Sequence of amino acids changes; tertiary structure
changes/folds in a different way; bonds form in different places
(not peptide);
Describe how two-way chromatography is carried out. [2]
Run chromatogram then turn through 90/right angle; With a
different solvent;
Explain the advantage of using two-way chromatography to
separate short polypeptides. [2]
Spreads spots/polypeptides out more/ make sure spot only
contains one substance;
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Describe how you would use a biochemical test to show that a
solution contained a non-reducing sugar, such as sucrose. [3]
,first reducing sugars test; boil with dilute HCl acid then
Neutralise with NaHCǑ, add benedict and heat to 95 degrees C
brick red ppt forms if reducing sugar is present
Describe a chemical test you could carry out to show that a
piece of coconut contains lipids. [3]
(Crush in) ethanol / alcohol; Add (to) water (Order of adding is
critical for this point); Emulsion / white colour
Explain what is meant by a polymer. [1]
Molecule) made up of many identical/similar
molecules/monomers/ subunits;
Name the reaction which occurs when starch is broken down
into maltose. [1]
Hydrolysis
What is the formula for lactose? [2]
C12 ; H22Ō1
,AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Describe how β-glucose molecule differs from a molecule of α-
glucose. [1]
H at top right end (instead of OH) / OH at bottom (carbon 1)
Show two ways in which the structure of cellulose is different
from the structure of starch. [2]
Starch 1,4 and 1,6 bonds / branching Cellulose 1,4 bonds / no
1,6 bonds / straight; starch All glucoses /monomers same way
up cellulose Alternate glucoses upside down; starch Helix /
coiled/compact cellulose Straight; Starch monomer Alpha
glucose Cellulose monomer Beta glucose
Describe the structure of starch and explain how its structure is
related to its function. [3]
Formed from α glucose; Joined by condensation/ by the
removal of a water molecule/ glycosidic bonds; Between
(carbons) 1 and 4 (and 1 and 6); Coiled chain; compact; (Allows)
storage of large amount in a small space; Insoluble so has no
effect on osmosis/water potential; Branches; (Allows) rapid
breakdown/release of glucose / hydrolysis;
,AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
The structure of a phospholipid molecule is different from that
of a triglyceride. Describe how. [2]
triglyceride has three fatty acids and phospholipid has two; no
phosphate group present in triglyceride but present in
phospholipid.
What is an unsaturated fatty acid? [1]
Some / two carbons with only one hydrogen / (double bonds)
between carbon atoms / not saturated with hydrogen;
Describe the structure of cellulose and explain how its structure
is related to its function. [3]
Alternate β-glucose rotated 180o, long straight chains, Many
hydrogen bonds join (polysaccharide) chains/molecules to each
other / makes microfibrils / gives tensile strength;
Which elements are found in proteins? [1]
Carbon, hydrogen, oxygen, nitrogen (sometimes sulphur)
Describe how you would use a biochemical test to show that a
solution contained protein. [2]
Biuret / alkali + copper sulphate; Lilac/purple/mauve/violet;
, AQA A LEVEL BIOLOGY REVISION QUESTIONS WITH
100% CORRECT VERIFIED ANSWERS UPDATED
2025/2026 BEST COMPLETE SOLUTION RATED A+
FOR SUCCESS
Which bonds are found in a)Primary structure [1]b)Secondary
structure [1] c)Tertiary structure [2]
a)Peptide b) Hydrogen (and peptide) c)Ionic, disulphide bridges,
hydrophobic interactions (hydrogen and peptide)
Explain how a change in the primary structure of a globular
protein may result in a different three-dimensional structure.
[3]
Sequence of amino acids changes; tertiary structure
changes/folds in a different way; bonds form in different places
(not peptide);
Describe how two-way chromatography is carried out. [2]
Run chromatogram then turn through 90/right angle; With a
different solvent;
Explain the advantage of using two-way chromatography to
separate short polypeptides. [2]
Spreads spots/polypeptides out more/ make sure spot only
contains one substance;
