Where do protons come from in electron transport chain?

Where do protons come from in electron transport chain?

Figure 1. The electron transport chain is a series of electron transporters embedded in the inner mitochondrial membrane that shuttles electrons from NADH and FADH2 to molecular oxygen. In the process, protons are pumped from the mitochondrial matrix to the intermembrane space, and oxygen is reduced to form water.

Why can electron carriers move a proton from one side of a membrane to the other?

Why can electron carriers move a proton from one side of a membrane to the other? They can accept an electron (along with an H+ from water) on one side of the membrane and then release the H+ on the other side of the membrane as they pass the electron to the next carrier.

Where does the Chemiosmosis occur?


Does photosynthesis use Chemiosmosis?

A photon strikes photosystem II to initiate photosynthesis. The ions flow through ATP synthase from the thylakoid space into the stroma in a process called chemiosmosis to form molecules of ATP, which are used for the formation of sugar molecules in the second stage of photosynthesis.

Why is it called Chemiosmosis?

This process is related to osmosis, the diffusion of water across a membrane, which is why it is called “chemiosmosis”. It allows protons to pass through the membrane and uses the free energy difference to phosphorylate adenosine diphosphate (ADP), making ATP.

What is the difference between Chemiosmosis in photosynthesis and cellular respiration?

Both cellular respiration and photosynthesis use chemiosmosis to create ATP. Chemiosmosis refers to specific steps within the electron transport chain utilized to create ATP. In cellular respiration, food is converted into ATP, while photosynthesis uses light energy to release ATP.

How does Chemiosmosis work in photosynthesis?

The light reactions use solar power to reduce NADP+ to NADPH by adding a pair of electrons along with an H+. The light reactions also generate ATP, using chemiosmosis to power the addition of a phosphate group to ADP, a process called photophosphorylation.

Which process of photosynthesis is linked to the production of ATP?

The Calvin cycle takes place in the stroma and uses the ATP and NADPH from the light-dependent reactions to fix carbon dioxide, producing three-carbon sugars—glyceraldehyde-3-phosphate, or G3P, molecules. The Calvin cycle converts ATP to ADP and Pi, and it converts NADPH to NADP+.

What are the photosystems I and II in photosynthesis?

There are two types of photosystems: photosystem I (PSI) and photosystem II (PSII). 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.

What is common to both photosystems I and II?

What is common to both photosystems I and II? In the photosystem I reaction center, light energy captured by pigment molecules is passed to a special reaction center chlorophyll a called: chlorophyll II.

What is the primary difference between photosystem I and II?

The main difference between photosystem 1 and 2 is that PS I absorbs longer wavelengths of light (>680 nm) whereas PS II absorbs shorter wavelengths of light (<680 nm).

What do both photosystems have in common?

The two photosystems have a common organisation and are functionally organised in two main moieties: a core complex, containing the reaction centre where the photochemical reactions occur, and a peripheral antenna system that increases the light harvesting capability, but that is also involved in regulation of the …

What color of light is not strongly absorbed by chlorophyll group of answer choices?

As shown in detail in the absorption spectra, chlorophyll absorbs light in the red (long wavelength) and the blue (short wavelength) regions of the visible light spectrum. Green light is not absorbed but reflected, making the plant appear green. Chlorophyll is found in the chloroplasts of plants.

Which wavelength of light is best absorbed by chlorophyll?

In the case of chlorophyll a the maximal absorption in the red region is at 642 nm and in the blue region at 372 nm; for chlorophyll b the values are 626 nm and 392 nm, respectively.

Which components of light are absorbed by chlorophyll?

Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to absorb energy from light. Chlorophyll absorbs light most strongly in the blue portion of the electromagnetic spectrum, followed by the red portion.

Which wavelengths of light are the most effective in photosynthesis?

The best wavelengths of visible light for photosynthesis fall within the blue range (425–450 nm) and red range (600–700 nm). Therefore, the best light sources for photosynthesis should ideally emit light in the blue and red ranges.

Why do plants absorb red and blue light?

Generally you can say that plants absorb primarily red (or red/orange) and blue light. It’s within the chloroplasts that all this light absorbing happens. The chloroplasts take the energy harnessed in these light rays and use it to make sugars for the plant to use in building more plant material = photosynthesis.

What is CO2 fixation?

Carbon fixation or сarbon assimilation is the process by which inorganic carbon (particularly in the form of carbon dioxide) is converted to organic compounds by living organisms. The compounds are then used to store energy and as structure for other biomolecules.

What light intensity and CO2 level is best for photosynthesis?

Photosynthesis increases as CO2 increases until some saturating concentration, which is typically around 1,000 ppm. Enriching the air with CO2 enables plants to more effectively utilize light, resulting in an increase in the light saturation point.

Why is there low oxygen flow in green light?

How does this explain the relatively low flow of oxygen in green light? The leaf doesn’t absorb the oxygen, so it reflects the green light, resulting in the low flow of oxygen.

Does more light mean more photosynthesis?

As you rise from low light intensity to higher light intensity, the rate of photosynthesis will increase because there is more light available to drive the reactions of photosynthesis. A limiting factor could be the amount of chlorophyll molecules that are absorbing the light.

Does a low oxygen environment change the rate of photosynthesis?

Oxygen inhibits photosynthesis in plants, even at O 2 levels as low as 2% or less (Björkman, 1966) . This phenomenon, known as the Warburg effect (Turner and Brittain, 1962), is exacerbated under conditions of low CO 2 , particularly under conditions of light saturation. …

How does photosynthesis affect oxygen levels quizlet?

As light intensity increases (distance between lamp and plant decreases) the volume of oxygen (or the rate of bubble production) increases. This indicates that the rate of photosynthesis increases with light intensity.

How does photosynthesis affect oxygen levels?

Through the photosynthetic process plants take up carbon dioxide and evolve oxygen. The present high concentration of molecular oxygen in the atmosphere is generally considered to have arisen from the activity of photo-synthetic organisms.

How does co2level affect oxygen production?

How does CO2 level affect oxygen production? increasing CO2 production increases oxygen production. Greater flow of oxygen corresponds to a higher rate of photosynthesis. Why would it be hard to find the ideal light intensity if the temperature were very hot or cold.

What would a low number of oxygen bubbles indicate about photosynthesis?

These bubbles can be counted and the rate of bubbling can serve as an indication of the rate of photosynthesis. When the light intensity is increased, the rate of bubble production should increase. The rate of photosynthesis should decrease and therefore the amount of oxygen bubbles should decrease.