AQA A LEVEL BIOLOGY EXAM QUESTIONS
PAPER 1 AND WORKED SOLUTIONS [100%
VERIFIED] LATEST EDITION 2026_2027
A biochemical test for reducing sugars produces a
negative result with raffinose solution. Describe a
biochemical test to show that raffinose solution
contains a non-reducing sugar. - correct answer - -
Add HCl, shake and heat
-Add sodium bicarbonate and shake to neutralise the
acid
-Add Benedict's solution and heat gently in a water
bath
-Positive result = brick red precipitate
,A change from Glu to Lys at amino acid 300 had no
effect on the rate of reaction catalysed by the enzyme.
The same change at amino acid 279 significantly
reduced the rate of reaction catalysed by the enzyme.
Use all the information and your knowledege of protein
structure to suggest reasons for the differences
between the effects of these two changes. - correct
answer - -Amino acid 300 was an intron so a mutation
wouldn't have affected the function of the enzyme.
-At amino acid 279 the change in the amino acid will
have caused a change in the sequence of the amino
acids. This will cause a change in the unique 3D
tertiary structure. The enzymes active site will change
shape.
-Negatively charged to positively charged change in
amino acid
A different student did this investigation. He did not
have a colorimeter.
Describe a method this student could use to prepare
colour standards and use them to give data for the
, total anthocyanin extracted - correct answer - -Use
known concentration of blueberry juice
-Prepare dilution series
-Compare with colour standards to give a
concentration
A journalist saw Figure 10 and suggested that future
increases in atmospheric carbon dioxide
concentration could result in less transpiration.
Evaluate his suggestion - correct answer - -Less
stomata, less water will evaporate
-Same CO₂ can be absorbed for photosynthesis
-Increasing CO₂ shows decreased stomatal density
-Don't know the size of stomata
A precipitate is produced in a positive result for
reducing sugar in a Benedict's test. A student carried
out a Benedict's test. Suggest a method, other than
using a colorimeter, that this student could use to
PAPER 1 AND WORKED SOLUTIONS [100%
VERIFIED] LATEST EDITION 2026_2027
A biochemical test for reducing sugars produces a
negative result with raffinose solution. Describe a
biochemical test to show that raffinose solution
contains a non-reducing sugar. - correct answer - -
Add HCl, shake and heat
-Add sodium bicarbonate and shake to neutralise the
acid
-Add Benedict's solution and heat gently in a water
bath
-Positive result = brick red precipitate
,A change from Glu to Lys at amino acid 300 had no
effect on the rate of reaction catalysed by the enzyme.
The same change at amino acid 279 significantly
reduced the rate of reaction catalysed by the enzyme.
Use all the information and your knowledege of protein
structure to suggest reasons for the differences
between the effects of these two changes. - correct
answer - -Amino acid 300 was an intron so a mutation
wouldn't have affected the function of the enzyme.
-At amino acid 279 the change in the amino acid will
have caused a change in the sequence of the amino
acids. This will cause a change in the unique 3D
tertiary structure. The enzymes active site will change
shape.
-Negatively charged to positively charged change in
amino acid
A different student did this investigation. He did not
have a colorimeter.
Describe a method this student could use to prepare
colour standards and use them to give data for the
, total anthocyanin extracted - correct answer - -Use
known concentration of blueberry juice
-Prepare dilution series
-Compare with colour standards to give a
concentration
A journalist saw Figure 10 and suggested that future
increases in atmospheric carbon dioxide
concentration could result in less transpiration.
Evaluate his suggestion - correct answer - -Less
stomata, less water will evaporate
-Same CO₂ can be absorbed for photosynthesis
-Increasing CO₂ shows decreased stomatal density
-Don't know the size of stomata
A precipitate is produced in a positive result for
reducing sugar in a Benedict's test. A student carried
out a Benedict's test. Suggest a method, other than
using a colorimeter, that this student could use to
