Exam 2 Flashcards
What are the two parts of photosynthesis?
The light-dependent reactions and the Calvin cycle.
The light-dependent reactions occur at the thylakoid membrane, while the Calvin cycle takes place in the stroma.
Where do the light-dependent reactions take place?
At the thylakoid membrane.
Chlorophyll absorbs energy from sunlight during these reactions.
What is the main function of chlorophyll in light-dependent reactions?
To absorb energy from sunlight and convert it into chemical energy using water.
What does the Calvin cycle utilize from the light-dependent reactions?
The chemical energy derived from the light-dependent reactions drives the capture of carbon and the assembly of sugar molecules.
What is a redox reaction?
Coupled reactions that involve a transfer of electrons.
What does oxidation refer to in a redox reaction?
Loss of electrons.
What does reduction refer to in a redox reaction?
Gain of electrons.
What does OIL RIG stand for?
Oxidation Is Loss, Reduction Is Gain.
What are electron carriers?
Mobile carriers for electrons that carry and move electrons around the cell.
What is NADP+ in the context of electron carriers?
Empty electron carrier.
What is NADPH in the context of electron carriers?
Loaded with electrons.
What are light-dependent reactions also known as?
Photolysis
What do light-dependent reactions convert?
Solar energy into chemical energy
What does the Calvin cycle use to make glucose?
Products of the light reactions
Where do light reactions occur?
In the thylakoid membranes
What do light reactions capture?
Light energy to create and store high energy molecules
What are the inputs of light reactions?
H2O and sunlight
What are the outputs of light reactions?
O2, ATP, and NADPH
When do light reactions occur?
During daylight hours
Where do dark reactions occur?
In the stroma
What do dark reactions use to build sugar?
Products of light reactions (ATP + NADPH)
What are the inputs of dark reactions?
CO2, ATP, and NADPH
What is the output of dark reactions?
Sugar, which is storable fuel
When do dark reactions occur?
24 hours a day
What is a photon?
A photon is the basic unit (particle) of light.
What happens when chlorophyll molecules absorb photons?
Electrons in chlorophyll gain energy and enter an unstable, excited state.
What occurs as electrons fall back to their ground state?
Energy is released as heat or light.
What is the function of a photosystem?
A photosystem acts as a light-gathering antenna that focuses light on a reaction center.
Where are photosystems located?
Photosystems are located on the thylakoid membrane.
What do aggregated pigments on the thylakoid membrane do?
They collect energy over a broad range of wavelengths and concentrate it on a reaction center.
What is the role of the reaction center in a photosystem?
The reaction center passes an electron to a series of enzymes.
What are the types of pigments found in photosystems?
Chlorophyll a, chlorophyll b, and carotenoids.
Photosynthesis equation
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
