Question

Put these steps in the order in which they occur in light-dependent reactions. Electrons are transferred from photosystem II to photosystem I. Light energy is absorbed and transferred to the reaction center. ATP is synthesized from ADP and inorganic phosphate. A water molecule is split.

Answer 1

Explanation:

1. Light energy is absorbed and transferred to the reaction center.
2. A water molecule is split.
3. Electrons are transferred from photosystem II to photosystem I.
4. ATP is synthesized from ADP and inorganic phosphate.

Further Explanation:

Photosynthesis is a chemical pathway that’s integral to producing energy in plants and other primary producers. Energy in the form of molecules of glucose is produced from light, water and carbon dioxide while oxygen is released. This occurs in several complex steps, photosynthesis is a rate limited reaction, depends on several factors including carbon dioxide concentration, ambient temperature and light intensity; the energy is retrieved from photons, I.e. particles of light, and water is used as a reducing agent. This occurs in the thykaloids, where pigment molecules like chlorophyll reside.

The chloroplast is a membrane bound organelle found in plants. It contains several invaginations of  a plasma membrane called the thylakoid membrane. This contains chlorophyll pigments, in stacks called granum, while the internal spaces of the organelle are called the lumen. Liquid surrounds the granum, forming the stroma.

During the light reaction:

• Light is absorbed by pigments in phosystem II (PSII). This energy is transferred among pigments til it gets to the reaction center, and is transferred to P680; this promotes an electron to a higher energy level where it then goes to an acceptor molecule.

• Water supplies the chlorophyll in plant cell with replacement electrons for the ones removed from photosystem II. Additionally, water (H2O) split by light during photolysis into H+ and OH- acts as a source of oxygen along with functioning as a reducing agent.
• the electron moves down an electron transport chain (ti PS I)where it experiences continuous energy loss. This energy fuels the pumping of H+ from the stroma to thykaloid, leading to the formation of a gradient. The H+ move along their gradient and cross through ATP synthase, into the the stroma.
• ATP synthase converts ADP and Pi to the energy storage molecule  ATP.
• The electron gets to photosystem I where it  goes to pigments at P700. It absorbs light energy, the electron is promoted to a higher energy level, and passed to an electron acceptor. This leaves a space for another electron which is then replaced by one from photosystem II.
• in the ETC,  the molecule NADP is reduced to NADPH by providing H+ ions. NADP and NADPH are integral to the Calvin cycle where monosaccharides or sugars like glucose are produced after the modification of several molecules.

Learn more about Photosynthesis at brainly.com/question/4216541

Learn more about cellular life at brainly.com/question/11259903

#LearnWithBrainly