Photosynthesis is a series of metabolic reactions that convert sunlight, water and CO2 into sugar and oxygen. The reactions in photosynthesis can be divided into light-dependent and light-independent reactions.
- The statement "photosystem II is used first then photosystem I" BEST describes how the photosystems are used in light-dependent reactions.
- Photosystem I (PSI) and photosystem (PSII) are protein complexes localized in the thylakoid membrane of the chloroplast.
- During light-dependent reactions, energy from sunlight is absorbed by chlorophyll of the photosystems. Subsequently, this energy is then converted into chemical energy (ATP and NADPH), a process that involves the transference of electrons.
- Both photosystem I and photosystem II contain pigments to collect sunlight energy and a reaction center in which excited electrons can be transferred from chlorophyll to an electron acceptor.
- Photosystem II is upstream in the electron flow pathway, but this photosystem (PSII) was discovered after photosystem I.
- Subsequently, electron flow is coupled to the generation of an electrochemical proton (H+) gradient across the thylakoid membrane, which is used to synthesize ATP by an ATP synthetase.
In conclusion, the statement "photosystem II is used first then photosystem I" BEST describes how the photosystems are used in light-dependent reactions.
Learn more in:
https://brainly.com/question/6233729?referrer=searchResults
