Light Reactions
What is the primary pigment involved in capturing light energy for photosynthesis?
Chlorophyll
What is the name of the enzyme that catalyzes the first step of the Calvin cycle?
Rubisco
What is the fluid-filled space surrounding the thylakoids where the Calvin cycle takes place?
Stroma
Which photosystem is responsible for producing ATP during the light reactions?
Photosystem II
How many molecules of CO₂ are needed to produce one molecule of G3P (glyceraldehyde-3-phosphate)?
3 molecules of CO₂
In what specific part of the chloroplast do the light-dependent reactions occur?
Thylakoid membrane
By the end of the light reactions what is formed?
NADPH
What molecule acts as the carbon acceptor that combines with CO₂ during the carbon fixation phase of the Calvin Cycle?
Ribulose bisphosphate (RuBP)
What is the name of the small compartments inside the thylakoid membranes where a proton gradient is established?
Thylakoid lumen
How many molecules of ATP and NADPH are used during one complete turn of the Calvin cycle to produce one G3P molecule?
9 ATP and 6 NADPH
Why do chloroplasts have their own DNA and ribosomes, and what does this suggest about their evolutionary history?
Chloroplasts have their own DNA and ribosomes because they are thought to have originated from an ancient symbiotic relationship with a photosynthetic prokaryote, supporting the endosymbiotic theory.
What happens during the regeneration phase of the Calvin cycle, and why is it crucial for the continuation of photosynthesis?
RuBP is regenerated from G3P using ATP, allowing the cycle to continue by providing the substrate (RuBP) necessary for further carbon fixation.
Explain how the structure of the thylakoid membrane is crucial for ATP synthesis during the light reactions.
The thylakoid membrane allows for the creation of a proton gradient by separating the thylakoid lumen from the stroma, which drives ATP synthesis via ATP synthase.