Photosynthesis Flashcards
Where are disc-like structures called thylakoids arranged within each chloroplast, and what are they known as?
Thylakoids are arranged in piles called grana.
What is the pigment found in the membrane of each thylakoid that absorbs light?
Chlorophyll
What is the fluid-filled space around the grana called?
The stroma
Where do the Light reactions take place, and what is required for them to occur?
Light reactions occur in the Thylakoid membrane and require constant solar energy.
Where do the Dark reactions occur, and do they require direct solar energy?
Dark reactions occur in the stroma and do not require direct solar energy.
What happens when a pigment absorbs a photon during photosynthesis?
When a pigment absorbs a photon, it is raised to an excited state, meaning that one of its electrons is boosted to a higher-energy orbital.
What is the function of the pigment molecules in a photosystem during photosynthesis?
Collectively, the pigment molecules collect energy and transfer it towards a central part of the photosystem called the reaction center.
What does the reaction center of a photosystem contain, and what are its properties?
The reaction center of a photosystem contains a unique pair of chlorophyll molecules called the special pair.
What happens once energy reaches the special pair in a photosystem during photosynthesis?
Once energy reaches the special pair, it passes an entire electron to the primary electron acceptor.
What happens to light collected by the special pair P680 during photosynthesis?
Light collected by special pair P680 donates an electron to the primary electron acceptor.
Describe the pathway of an electron leaving Photosystem II (PSII) in the Electron Transport Chain.
When an electron leaves PSII, it is transferred first to plastoquinone (Pq), then to a cytochrome complex (Cyt), and finally to plastocyanin (Pc).
How is energy utilized as an electron travels in the Electron Transport Chain during photosynthesis?
As the electron travels, some of the energy is used to pump protons across the stroma to the thylakoid lumen.
What is formed as a result of the transfer of protons and the release of H+ from the splitting of water during photosynthesis?
The transfer of protons and the release of H+ form a proton gradient.
Describe the role of protons moving down their concentration gradient during photosynthesis.
Protons move down their concentration gradient through ATP synthase, creating ATP.
What occurs in the Light-Independent Reactions (LIR) of photosynthesis?
. In the LIR, carbon atoms from CO2 are fixed and used to build glucose.
