AQA A Level Biology Paper 1
AQA A Level Biology Paper 1 Exam
Containing 208 Questions and Answers
2024-2025.
Water removed from the reactants joining two molecules together forming a
chemical bond - Answer: Condensation
The addition of water to the reactants to break a chemical bond between 2
molecules - Answer: Hydrolysis
1
, AQA A Level Biology Paper 1
1. Add Benedict's reagent. 2. Heat the solution in a water bath for 5 minutes at 95
degrees Celsius. 3. Change from blue to brick red as CuO formed - Answer: Test
for Reducing Sugars (3)
Smaller units from which larger molecules are made - Answer: Monomer
1. Add 2cm³ of food sample then add 2cm³ of dilute HCl and heat.
2. Add 2cm³ of NaHCO3 then do test for reducing sugars. - Answer: Non-Reducing
Sugars (2)
Add drops of iodine to starch solution. Colour change to blue-black - Answer: Test
for Starch (1)
1. Mix Test solution with ethanol.
2. Shake for 1 minute then add water.
3. Cloudy white emulsion - Answer: Test for Lipids (3)
1. Obtain equal volumes of test solution and NaOH then add a few drops of biuret
solution (dilute copper (II) sulphate solution).
2. Colour change to mauve/purple - Answer: Test for Proteins (2)
1. Very high resolution.
2. Needs thin and dead specimen.
3. Artefacts can occur (remnant left on object during prep, such as air bubbles)
2
, AQA A Level Biology Paper 1
4. Uses magnets to focus on specimen
5. Uses electrons fired at sample.
6. Is not in colour - Answer: Transmission Electron Microscope (5)
1. Inhibitor is similar in shape to substrate so it impermanently binds to the active
site.
2. Prevents ESC from forming, slowing rate - Answer: Competitive inhibition (2)
1. Molecule will bind to allosteric site.
2. Binding causes a change in active site.
3. Permanently preventing further ESC. - Answer: Non-competitive inhibition (3)
1. DNA helicase breaks the hydrogen bonds between the base pairs
2. 2 single strands formed as the double helix "unzips".
3. Free DNA nucleotides in the nucleoplasm bond to the complementary bases on
the strand.
4. DNA polymerase forms phosphodiester bonds between adjacent DNA
nucleotides via condensation reaction with the hydrolysis of ATP, forming the
phosphate backbone - Answer: DNA Replication: Semiconservative (4)
1. ATP stores or releases only a small amount of energy at a time, so no energy is
wasted as heat.
2. Small and soluble so easily transported
3. Easily broken down, so energy is released instantaneously
4. Can be quickly re-made
3
, AQA A Level Biology Paper 1
5. Can make other molecules more reactive via phosphorylation
6. ATP can't pass out of cell, so the cell always has an immediate supply of energy.
- Answer: Describe 6 properties of ATP that make it a good energy source. (6)
Prevents the cell from drying out. Allows bacteria to stick to each other - Answer:
Slime capsule (2)
Used for attachment of a cell to a surface - Answer: Fimbria
Involved in bacterial conjugation - Answer: Pilli
Invagination of cell membrane. Site of cell respiration (prokaryotes) - Answer:
Mesosome
The ability to distinguish two points apart - Answer: Resolution
1. Lower resolution than TEM
2. 3D image
3. Does not require thin samples - Answer: Scanning Electron Microscope
The mass of organelles at the bottom of the test tube after centrifugation. -
Answer: Pellet
Cold. Low temperature slows enzyme activity, minimising self digestion by
reducing metabolic rate. Isotonic. Salt and sugar concentration kept the same,
4
AQA A Level Biology Paper 1 Exam
Containing 208 Questions and Answers
2024-2025.
Water removed from the reactants joining two molecules together forming a
chemical bond - Answer: Condensation
The addition of water to the reactants to break a chemical bond between 2
molecules - Answer: Hydrolysis
1
, AQA A Level Biology Paper 1
1. Add Benedict's reagent. 2. Heat the solution in a water bath for 5 minutes at 95
degrees Celsius. 3. Change from blue to brick red as CuO formed - Answer: Test
for Reducing Sugars (3)
Smaller units from which larger molecules are made - Answer: Monomer
1. Add 2cm³ of food sample then add 2cm³ of dilute HCl and heat.
2. Add 2cm³ of NaHCO3 then do test for reducing sugars. - Answer: Non-Reducing
Sugars (2)
Add drops of iodine to starch solution. Colour change to blue-black - Answer: Test
for Starch (1)
1. Mix Test solution with ethanol.
2. Shake for 1 minute then add water.
3. Cloudy white emulsion - Answer: Test for Lipids (3)
1. Obtain equal volumes of test solution and NaOH then add a few drops of biuret
solution (dilute copper (II) sulphate solution).
2. Colour change to mauve/purple - Answer: Test for Proteins (2)
1. Very high resolution.
2. Needs thin and dead specimen.
3. Artefacts can occur (remnant left on object during prep, such as air bubbles)
2
, AQA A Level Biology Paper 1
4. Uses magnets to focus on specimen
5. Uses electrons fired at sample.
6. Is not in colour - Answer: Transmission Electron Microscope (5)
1. Inhibitor is similar in shape to substrate so it impermanently binds to the active
site.
2. Prevents ESC from forming, slowing rate - Answer: Competitive inhibition (2)
1. Molecule will bind to allosteric site.
2. Binding causes a change in active site.
3. Permanently preventing further ESC. - Answer: Non-competitive inhibition (3)
1. DNA helicase breaks the hydrogen bonds between the base pairs
2. 2 single strands formed as the double helix "unzips".
3. Free DNA nucleotides in the nucleoplasm bond to the complementary bases on
the strand.
4. DNA polymerase forms phosphodiester bonds between adjacent DNA
nucleotides via condensation reaction with the hydrolysis of ATP, forming the
phosphate backbone - Answer: DNA Replication: Semiconservative (4)
1. ATP stores or releases only a small amount of energy at a time, so no energy is
wasted as heat.
2. Small and soluble so easily transported
3. Easily broken down, so energy is released instantaneously
4. Can be quickly re-made
3
, AQA A Level Biology Paper 1
5. Can make other molecules more reactive via phosphorylation
6. ATP can't pass out of cell, so the cell always has an immediate supply of energy.
- Answer: Describe 6 properties of ATP that make it a good energy source. (6)
Prevents the cell from drying out. Allows bacteria to stick to each other - Answer:
Slime capsule (2)
Used for attachment of a cell to a surface - Answer: Fimbria
Involved in bacterial conjugation - Answer: Pilli
Invagination of cell membrane. Site of cell respiration (prokaryotes) - Answer:
Mesosome
The ability to distinguish two points apart - Answer: Resolution
1. Lower resolution than TEM
2. 3D image
3. Does not require thin samples - Answer: Scanning Electron Microscope
The mass of organelles at the bottom of the test tube after centrifugation. -
Answer: Pellet
Cold. Low temperature slows enzyme activity, minimising self digestion by
reducing metabolic rate. Isotonic. Salt and sugar concentration kept the same,
4
