Part One

Question 1

What is the general balanced equation for photosynthesis?

Answer 1

6CO2 + 6H2O —> glucose + 6O2

Question 2

Is photosynthesis endergonic or exergonic? Explain

Answer 2

Endergonic, because it needs energy to happen. Plants use sunlight to turn carbon dioxide and water into glucose (sugar) and oxygen. The sunlight provides the energy needed for this process.

Question 3

What is the main function of CO2 in photosynthesis?

Answer 3

• CO₂ reacts with RuBP (catalyzed by RuBisCO) in the Calvin cycle.
• This forms a 3-carbon compound called 3-phosphoglycerate.
• Through a series of reactions, it is converted into glucose, which provides energy for the plant.

Question 4

What is the main function of H2O in photosynthesis?

Answer 4

• H₂O provides electrons and protons needed for energy production in photosynthesis.
• Splitting of H₂O releases electrons for making ATP and NADPH.
• Oxygen is released as a byproduct when H₂O is split.

Question 5

Where does the O2 molecule come from during photosynthesis?

Answer 5

• O₂ comes from splitting water molecules during photosynthesis.
• This process, called photolysis, happens in the chloroplasts.
• Splitting water provides electrons and protons for energy production.
• Oxygen is released as a byproduct and contributes to the atmosphere’s oxygen.