How does photosynthesis convert solar energy into chemical energy?
Photosynthesis converts solar energy into chemical energy that plants use to make glucose so they can grow.
What is the role of light energy in photosynthesis?
Light energy oxidizes the reaction center chlorophyll and transfers electrons to an electron transport chain, which generates a proton gradient across the photosynthetic membrane. The terminal electron acceptors in purple bacteria are the oxidized reaction center chlorophylls; the electrons flow in a cycle from PSII down the ETC back to PSII.
How do photosystems work?
Photosystems are membrane complexes of proteins and chlorophyll molecules. The chlorophyll molecules absorb photons and funnel the energy to a reaction center chlorophyll, which becomes oxidized (loses electrons).
How do organisms use light energy for conversion to chemical energy?
Organisms that capture light energy for conversion to chemical energy show evolutionary and phylogenetic differences in the pigments they use. Phototrophic organisms convert light energy into chemical energy in the form of ATP. The use of light energy to make ATP is called photophosphorylation.
Which of the process converts light energy to chemical energy?
PhotosynthesisPhotosynthesis is a process by which green plants and certain other organisms synthesise their own food i.e. transform sunlight energy into chemical energy with the help of chlorophyll, carbon dioxide and water.
How is light energy converted into chemical energy during photosynthesis quizlet?
B. How is light energy converted into chemical energy during photosynthesis? Light energy absorbed by pigments produces high-energy electrons that are used to convert NADP+ and ADP to the compounds NADPH and ATP, trapping the energy in chemical form.
How does a photosystem convert energy from one form to another?
A photon of light energy travels until it reaches a molecule of chlorophyll. The photon causes an electron in the chlorophyll to become “excited.” The energy given to the electron allows it to break free from an atom of the chlorophyll molecule.
How is light energy converted into chemical energy in the light dependent stage?
In light-dependent reactions, the energy from sunlight is absorbed by chlorophyll and converted into chemical energy in the form of electron carrier molecules like ATP and NADPH. Light energy is harnessed in Photosystems I and II, both of which are present in the thylakoid membranes of chloroplasts.
How is most energy transferred through a photosystem?
Most of the pigments in a photosystem act as an energy funnel, passing energy inward to a main reaction center. When one of these pigments is excited by light, it transfers energy to a neighboring pigment through direct electromagnetic interactions in a process called resonance energy transfer.
What is the process of photosystem?
The process of photosynthesis: the conversion of light energy to ATP. The electron transfers of the light reactions provide the energy for the synthesis of two compounds vital to the dark reactions: NADPH and ATP. The previous section explained how noncyclic electron flow results in the reduction of NADP+ to NADPH.
How does photosystem 2 replace its electrons?
Within the photosystem, enzymes capture photons of light to energize electrons that are then transferred through a variety of coenzymes and cofactors to reduce plastoquinone to plastoquinol. The energized electrons are replaced by oxidizing water to form hydrogen ions and molecular oxygen.
What type of energy is converted to chemical energy in photosynthesis quizlet?
Because during photosynthesis, light energy is converted into chemical energy which is stored in glucose.
Which of the following is converted into chemical energy during photosynthesis quizlet?
Producers, through the process photosynthesis, turn sunlight into chemical energy in the form of simple sugars. During photosynthesis, solar energy is turned into chemical energy in the form of glucose, a simple sugar.
Where does the conversion of light energy to chemical energy take place quizlet?
Photosynthesis is the process by which light energy is converted into chemical energy. Photosynthesis occurs in the chloroplasts, located in the leaf. Chlorophyll makes leaves green and is what captures light energy.
What type of photosystem does purple bacteria have?
Bacteria that have only a type II photosystem (PSII), such as the purple bacteria are phototropic: they use light energy to make ATP by photophosphorylation, but they do not use light energy to fix carbon dioxide. Photophosphorylation is very much like oxidative phosphorylation. In both, a membrane-localized ATP synthase complex uses power from a proton gradient to make ATP. Light energy oxidizes the reaction center chlorophyll and transfers electrons to an electron transport chain, which generates a proton gradient across the photosynthetic membrane. The terminal electron acceptors in purple bacteria are the oxidized reaction center chlorophylls; the electrons flow in a cycle from PSII down the ETC back to PSII. Purple sulfur bacteria with only PSII cannot use light energy to make NADH or NADPH, but they can use other pathways to oxidize hydrogen sulfide as a source of electrons to make reduced electron carriers. In other words, purple sulfur bacteria can fix carbon dioxide, but they cannot use their photosystem II to do it; their photosystem II can only be used to make ATP.
How does chlorophyll make ATP?
The oxidized reaction center chlorophyll pulls electrons from H2S down the photosynthetic electron transport chain, which generates a proton gradient to make ATP. Thus green-sulfur bacteria use light energy to produce both ATP and reducing power; both are required for carbon fixation (reduction of CO2 to carbohydrate).
What is the energy used by photoautotrophs?
Photosynthetic organisms (photoautotrophs) use light energy to make both ATP and reduced electron carriers (NADH or NADPH). The reduction of carbon dioxide (CO2) to carbohydrate (CH2O) requires both ATP and reducing power in the form of NADPH or NADH (NADP+ is NAD+ with a phosphate group added, and is used by chloroplasts instead of NAD+).
What is the protein that reduces NADP+ to NADPH?
Photosystem I, when it becomes oxidized by absorbing light energy, transfers electrons to a protein called ferredoxin, which in turn reduces NADP+ to NADPH. NADP+ is an electron carrier, a phosphorylated form of NAD+; it may help to think of the P as standing for photosynthesis.
How do green sulfur bacteria use light energy?
Bacteria with only a type I photosystem (PSI), such as green-sulfur bacteria, can be true photoautotrophs: they use light energy both to make ATP and to fix (reduce) carbon dioxide. Light energy oxidizes the reaction center chlorophyll, which reduces the the electron carrier NAD+ to make NADH. The oxidized reaction center chlorophyll must then be reduced by electrons from a chemical electron donor, such as hydrogen sulfide (H2S). The oxidized reaction center chlorophyll pulls electrons from H2S down the photosynthetic electron transport chain, which generates a proton gradient to make ATP. Thus green-sulfur bacteria use light energy to produce both ATP and reducing power; both are required for carbon fixation (reduction of CO2 to carbohydrate). However, they are limited by the availability of a suitable electron donor such as H2S.
Which photosystems absorb photons and funnel energy to a reaction center?
The chlorophyll molecules absorb photons and funnel the energy to a reaction center chlorophyll, which becomes oxidized (loses electrons). All oxygenic photosynthesizers (those that produce oxygen gas as a byproduct; cyanobacteria and chloroplasts) have two different types of photosystems coupled together.
What is the chemical equation for photosynthesis?
The overall chemical equation for oxygenic photosynthesis is: 6 CO2 + 12 H2 O –> C6H12O6 + 6 O 2 + 6 H2O.
