Question: Where Does Photosystem 2 Get Its Electrons?

What is the main role of photosystem I?

Photosystem I is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin.

Ultimately, the electrons that are transferred by Photosystem I are used to produce the high energy carrier NADPH..

What is the ultimate source of electrons in photosynthesis?

In photosynthesis, water is the source of electrons and their final destination is NADP+ to make NADPH.

How does photosystem 2 replenish its electrons?

Photosystem II (or water-plastoquinone oxidoreductase) is the first protein complex in the light-dependent reactions of oxygenic photosynthesis. … The energized electrons are replaced by oxidizing water to form hydrogen ions and molecular oxygen.

Where does photosystem 1 get its electrons?

Photosystem I receives electrons from plastocyanin or cytochrome c6 on the lumenal side of the thylakoid membrane and uses light energy to transfer them across the membrane to ferredoxin on the stromal side. It can also function in a cyclic electron transport pathway.

What is the purpose of photosystem 2?

Photosystem II (PS II) is a pigment-protein complex in thylakoid membranes from all oxygenic photosynthetic organisms (cyanobacteria and photosynthetic eukaryotes). It catalyzes the light-induced reduction of plastoquinone by water through a number of redox reactions.

What is the function of photosystem I?

Photosystem I, a membrane protein complex found in all oxygenic photosynthetic organisms, uses light energy to transfer electrons from plastocyanin to ferredoxin. Light energy captured by antenna chlorophylls is transferred rapidly to the primary electron donor, P700.

What happens when photosystem II is inhibited?

In general, these herbicides inhibit photosynthesis by binding to D1 proteins of the photosystem II complex in chloroplast thylakoid membranes. … In addition, some PSII Inhibitors affect other plant processes such as carotenoid biosynthesis and synthesis of anthocyanin, RNA, and proteins.

What is the source of the electrons in photosynthesis?

Photosynthesis in green plants takes place in chloroplasts (Figure 19.1). The energy of light captured by pigment molecules, called chlorophylls, in chloroplasts is used to generate high-energy electrons with great reducing potential.

What is the main function of photosystem II?

Photosystem II (PSII) is a multi-component pigment-protein complex that is responsible for water splitting, oxygen evolution, and plastoquinone reduction.

Does photosystem 2 produce oxygen?

Photosystem II is the first membrane protein complex in oxygenic photosynthetic organisms in nature. It produces atmospheric oxygen to catalyze the photo-oxidation of water by using light energy. It oxidizes two molecules of water into one molecule of molecular oxygen.

Where does photosystem 2 take an electron?

The heart of photosystem II is the reaction center, where the energy of light is converted into the motion of energized electrons. At the center is a key chlorophyll molecule. When it absorbs light, one of its electrons is promoted to a higher energy.

What is the final product of photosystem 2?

Photosystem II obtains replacement electrons from water molecules, resulting in their split into hydrogen ions (H+) and oxygen atoms. The oxygen atoms combine to form molecular oxygen (O2), which is released into the atmosphere.

What would happen if photosystem 2 stopped working?

what does photosystem II produce? … What would happen to the concentrations of ATP, NADPH and Sugars if PSII stopped working? ATP, NADP and sugars would decrease. What would happen to the concentrations of ATP, NADPH and Sugars if PSI stopped working?

Where do plants get their electrons from?

chloroplastsThe process takes place in chloroplasts, the cellular powerhouses that make sugars and give leaves and algae their green color. In the chloroplasts, water is split into oxygen, protons and electrons. Sunlight penetrates the chloroplast and zaps the electrons to a high energy level, and a protein promptly grabs them.

What two main products result from photosynthesis?

In photosynthesis, energy from light is used to convert carbon dioxide and water into glucose and oxygen.

What is the difference between photosystem 1 and 2?

The two main multi-subunit membrane protein complexes differ in their absorbing wavelength, where the photosystem I or PS 1 absorbs the longer wavelength of light which is 700 nm while photosystem II or PS 2 absorbs the shorter wavelength of light 680 nm.

What are photosystem 1 and 2?

Both photosystems contain many pigments that help collect light energy, as well as a special pair of chlorophyll molecules found at the core (reaction center) of the photosystem. The special pair of photosystem I is called P700, while the special pair of photosystem II is called P680.

Does photosystem 2 produce ATP?

Electrons are transferred sequentially between the two photosystems, with photosystem I acting to generate NADPH and photosystem II acting to generate ATP. … Electron transport through photosystem II is thus coupled to establishment of a proton gradient, which drives the chemiosmotic synthesis of ATP.