0
In very general terms, electron transfer is caused by photoexcitation of the pigment molecules in the antenna complex. The chlorophyll and carotenoid molecules in the antenna complex become photoexcited when they absorb any wavelengths of visible light and then transmit resonant energy.
What else can I help you with?
What happens to electrons when pigments in photosystem II absorbs light?
they move through an electron transport chain to photosystem 1
Where do the high-energy electrons carried by NADPH come from?
Photosystem 1
Electrons are excited in photosystem 1 what do these electrons combine with in order to produce an energy-carrying molecule?
NADP+
What protein complex absorbs in energy that used to produce NADPH?
Photosystem 1
How do electrons gain in energy in photosystem 1?
they absorb photons from sunlight
How does electrons move photosytem II to photosytem?
Electrons move from Photosystem II to Photosystem I through a series of electron carrier molecules in the thylakoid membrane, known as the electron transport chain. During photosynthesis, light energy is used to transfer electrons along this chain, creating a proton gradient that drives ATP synthesis. This process is essential for the production of energy-rich molecules in the form of ATP and NADPH.
Where do electrons get their energy in photosystem II?
From energy in photons
Which sentence best describes what happens after sunlight hits photo system 2?
After sunlight hits photosystem 2, it excites electrons within photosystem 2. These electrons are then passed down an electron transport chain to photosystem 1, where they help generate ATP through a series of redox reactions.
How many times are electrons energized during photosynthesis?
The thylakoid membrane contains 2 photosytems, known as Photosystem I and Photosystem II. Together, they function to absorb light and transfer energy to electrons.
Where do the electron get their energy in photosystem 1?
They pass through a series of compounds to photosystem I, losing energy along the way. Photosystem I, like photosystem II, emits high-energy electrons in the light, and the electrons from photosystem II replace these. Photosystem II contains chlorophyll molecules. When a photon (quantum of light) reaches one of these chlorophyll molecules, the light energy activates an electron. This is then passed to the reaction center of the photosystem, where there are two molecules of chlorophyll P680. These pass the electrons to plastoquinone, which, like the chlorophylls, is embedded in the thylakoid membrane. The plastoquinone changes its position within the membrane, and passes the electrons to cytochromes b6 and f. At this stage the electrons part with a significant proportion of their energy, which is used to pump protons (H+) into the thylakoid lumen. These protons will later be used to generate ATP by chemiosmosis. The electrons now pass to plastocyanin, which is outside the membrane on the lumen side. Photosystem I is affected by light in much the same way as photosystem II. Chlorophyll P700 passes an activated electron to ferredoxin, which is in the stroma (the liquid outside the thylakoid). Ferredoxin in turn passes the electrons on, reducing NADP+ to NADPH + H+. Photosystem I accepts electrons from plastocyanin. So, effectively, photosystem II donates electrons to photosystem I, to replace those lost from photosystem I in sunlight. How does photosystem II recover electrons? When it loses an electron, photosystem II becomes an oxidizing agent, and splits water: 2H2O forms 4H+ + 4e- + O2. The electrons return photosystem II to its original state, and the protons add to the H+ concentration in the thylakoid lumen, for later use in chemiosmosis. The oxygen diffuses away.
What sequence accurately reflects the flow of electrons in photosynthesis?
In photosynthesis, electrons flow from water molecules to photosystem II, then to photosystem I, and finally to NADP+ ultimately producing NADPH. Along the way, the electrons generate a proton gradient that drives ATP production.
What happens to electrons when pigments in photosystem absorb lights?
Photosystem's electron travel through the electron transport chain(etc) where ATP is produced and then back to the photosystem. In non-cyclic photophosphorylation, Photosystem II electron then is absorbed by photosystem I, photosystem I electron used to form NADPH and photosystem II gets its electron from photolysis of water. For you unfortunate children using Novanet: They move through an electron transport chain to photosystem 1.
