Where does photosynthesis mainly occur in plants?
In the leaves, specifically in chloroplasts.
What is a photon?
A particle of light that acts as a bundle of energy.
What are the two main parts of a photosystem?
The antenna complex and the reaction center.
Where does the Calvin cycle take place?
In the stroma of the chloroplast.
What are the two activities of Rubisco?
Carboxylation (adds CO₂) and oxygenation (adds O₂).
Which organisms carry out oxygenic photosynthesis?
Cyanobacteria, algae, and land plants.
What happens to photon energy as wavelength decreases?
Energy increases.
What happens in the antenna complex?
Light is absorbed and transferred to the reaction center.
What enzyme catalyzes CO₂ fixation?
Rubisco (RuBP carboxylase/oxygenase).
Why is photorespiration inefficient?
It uses ATP and NADPH without producing glucose.
What gas do plants release during photosynthesis?
Oxygen
What are the two main pigment types in plants?
Chlorophylls and carotenoids.
What occurs during the primary photo event?
A photon excites an electron in a pigment molecule.
What are the three phases of the Calvin cycle?
Carbon fixation, reduction, regeneration of RuBP.
How do C3 and C4 plants differ?
C4 plants use PEP carboxylase and separate carbon fixation spatially.
Which gas do plants take in for photosynthesis?
Carbon dioxide (CO₂).
What is the main role of chlorophyll a?
Converts light energy to chemical energy.
What are the final products of noncyclic photophosphorylation?
ATP, NADPH, and O₂.
How many turns are needed to make one glucose molecule?
Six turns.
When do CAM plants fix CO₂?
At night, storing it as organic acids for daytime use.
What are the two main stages of photosynthesis?
The light-dependent reactions and the Calvin cycle (light-independent reactions).
Why are carotenoids important besides absorbing light?
They act as antioxidants, protecting from reactive oxygen species.
Which photosystem is used in cyclic photophosphorylation?
Photosystem I only.
What are the main inputs for the Calvin cycle?
ATP, NADPH, and CO₂.
How do C4 and CAM plants reduce photorespiration?
By increasing CO₂ near Rubisco — C4 spatially, CAM temporally.