AQA A Level Biology Paper 1
ACTUAL EXAM QUESTIONS
AND CORRECT ANSWERS
LATEST UPDATE
WHAT TO FIND IN THIS EXAM
➢CASE STUDIES NGN STYLE QUESTIONS
➢BUTTERFLY QUESTION WITH ANSWERS
➢WELL, EXPLAINED ANSWERS
➢ VERIFIED EXPLANATIONS AND ANSWERS
➢ GRADE A+ ACTUAL EXAM
,Question: What is the process called when water is removed
from reactants to join two molecules together?
Answer: Condensation
Question: What is the process called when water is added to
break a chemical bond between two molecules?
Answer: Hydrolysis
Question: How do you test for reducing sugars?
Answer:
1. Add Benedict’s reagent to the sample.
2. Heat in a water bath at 95°C for 5 minutes.
3. A color change from blue to brick red indicates reducing
sugars (CuO formation).
Question: How do you test for non-reducing sugars?
Answer:
1. Add 2 cm³ of the food sample and 2 cm³ of dilute
hydrochloric acid, then heat.
, 2. Neutralize with sodium hydrogen carbonate.
3. Repeat the Benedict’s test for reducing sugars.
Question: How do you test for starch?
Answer: Add iodine solution to the sample. A blue-black
color indicates starch.
Question: How do you test for lipids using the emulsion test?
Answer:
1. Mix the test solution with ethanol.
2. Shake for 1 minute and then add water.
3. A cloudy white emulsion indicates the presence of lipids.
Question: How do you test for proteins using the Biuret test?
Answer:
1. Add equal volumes of the test solution and sodium
hydroxide.
2. Add a few drops of Biuret reagent (dilute copper(II)
sulfate).
3. A mauve or purple color indicates proteins.
, Question: What are monomers?
Answer: Monomers are smaller units that join together to
form larger molecules (polymers).
Question: Describe the process of DNA replication using the
semiconservative model.
Answer:
1. DNA helicase breaks hydrogen bonds, unzipping the
double helix.
2. Free DNA nucleotides pair with complementary bases.
3. DNA polymerase forms phosphodiester bonds via a
condensation reaction using ATP.
4. Two identical DNA strands form, each with one original
and one new strand.
Question: What properties make ATP a good energy source?
Answer:
• Releases only small amounts of energy at a time, reducing
heat loss.
• Small and soluble, so easily transported.
ACTUAL EXAM QUESTIONS
AND CORRECT ANSWERS
LATEST UPDATE
WHAT TO FIND IN THIS EXAM
➢CASE STUDIES NGN STYLE QUESTIONS
➢BUTTERFLY QUESTION WITH ANSWERS
➢WELL, EXPLAINED ANSWERS
➢ VERIFIED EXPLANATIONS AND ANSWERS
➢ GRADE A+ ACTUAL EXAM
,Question: What is the process called when water is removed
from reactants to join two molecules together?
Answer: Condensation
Question: What is the process called when water is added to
break a chemical bond between two molecules?
Answer: Hydrolysis
Question: How do you test for reducing sugars?
Answer:
1. Add Benedict’s reagent to the sample.
2. Heat in a water bath at 95°C for 5 minutes.
3. A color change from blue to brick red indicates reducing
sugars (CuO formation).
Question: How do you test for non-reducing sugars?
Answer:
1. Add 2 cm³ of the food sample and 2 cm³ of dilute
hydrochloric acid, then heat.
, 2. Neutralize with sodium hydrogen carbonate.
3. Repeat the Benedict’s test for reducing sugars.
Question: How do you test for starch?
Answer: Add iodine solution to the sample. A blue-black
color indicates starch.
Question: How do you test for lipids using the emulsion test?
Answer:
1. Mix the test solution with ethanol.
2. Shake for 1 minute and then add water.
3. A cloudy white emulsion indicates the presence of lipids.
Question: How do you test for proteins using the Biuret test?
Answer:
1. Add equal volumes of the test solution and sodium
hydroxide.
2. Add a few drops of Biuret reagent (dilute copper(II)
sulfate).
3. A mauve or purple color indicates proteins.
, Question: What are monomers?
Answer: Monomers are smaller units that join together to
form larger molecules (polymers).
Question: Describe the process of DNA replication using the
semiconservative model.
Answer:
1. DNA helicase breaks hydrogen bonds, unzipping the
double helix.
2. Free DNA nucleotides pair with complementary bases.
3. DNA polymerase forms phosphodiester bonds via a
condensation reaction using ATP.
4. Two identical DNA strands form, each with one original
and one new strand.
Question: What properties make ATP a good energy source?
Answer:
• Releases only small amounts of energy at a time, reducing
heat loss.
• Small and soluble, so easily transported.
