A-LEVEL BIOLOGY PAPER 1 EXAM PREP
2026 TEST PAPER QUESTIONS AND
SOLUTIONS GUARANTEED TO PASS
⩥ What is the purpose of photosynthesis? Answer: To energy from light
is used to make glucose
⩥ What is the general equation for photosynthesis ? Answer: 6H2O +
6CO2 + energy --> C6H12O6 + 6O2
⩥ What are the x stages of the light dependent reaction ? Answer: 1.
Photoionisation of PSII
2. Photolysis of water
3. Photoionisation of PSI
4. Active transport of H+ ions
5. Oxidative phosphorylation
6. Reducing NADP
⩥ Describe what happens during photoionisation of PSII Answer:
Chlorophyll absorbs light
Electrons excited and move to higher energy level
Electrons move down electron transport chain to PSI
, ⩥ Describe what happens during photolysis of water Answer: Light
energy splits water molecules into H+, e- and oxygen
The electrons replace those lost from PSII during photoionisation
⩥ Explain how H+ ions are moved across the thylakoid membrane
Answer: The excited electrons from photoionisation lose energy as they
move down the electron transport chain
The energy is used to actively transport H+ into the chloroplast
⩥ Explain how H+ are involved in the synthesis of ATP in chloroplasts
Answer: H+ move down their concentration gradient into the stroma
This is via ATP synthase in the thylakoid membrane
The energy synthesises ATP from ADP and Pi
⩥ Explain why the photoionisation of PSI is important Answer: The
excited eletrons are transferred to NADP with H+ to form reduced
NADP
This is needed for the light-independent reaction
⩥ What is chemiosmosis ? Answer: Electrons move down the electron
transport chain and creating a proton gradient
This drived ATP synthesis
2026 TEST PAPER QUESTIONS AND
SOLUTIONS GUARANTEED TO PASS
⩥ What is the purpose of photosynthesis? Answer: To energy from light
is used to make glucose
⩥ What is the general equation for photosynthesis ? Answer: 6H2O +
6CO2 + energy --> C6H12O6 + 6O2
⩥ What are the x stages of the light dependent reaction ? Answer: 1.
Photoionisation of PSII
2. Photolysis of water
3. Photoionisation of PSI
4. Active transport of H+ ions
5. Oxidative phosphorylation
6. Reducing NADP
⩥ Describe what happens during photoionisation of PSII Answer:
Chlorophyll absorbs light
Electrons excited and move to higher energy level
Electrons move down electron transport chain to PSI
, ⩥ Describe what happens during photolysis of water Answer: Light
energy splits water molecules into H+, e- and oxygen
The electrons replace those lost from PSII during photoionisation
⩥ Explain how H+ ions are moved across the thylakoid membrane
Answer: The excited electrons from photoionisation lose energy as they
move down the electron transport chain
The energy is used to actively transport H+ into the chloroplast
⩥ Explain how H+ are involved in the synthesis of ATP in chloroplasts
Answer: H+ move down their concentration gradient into the stroma
This is via ATP synthase in the thylakoid membrane
The energy synthesises ATP from ADP and Pi
⩥ Explain why the photoionisation of PSI is important Answer: The
excited eletrons are transferred to NADP with H+ to form reduced
NADP
This is needed for the light-independent reaction
⩥ What is chemiosmosis ? Answer: Electrons move down the electron
transport chain and creating a proton gradient
This drived ATP synthesis
