(a) which compounds donate electrons to the electron transport chain?

The reduced coenzymes generated by the citric acid cycle donate electrons in a series of reactions called the electron transport chain. The energy from the electron transport chain is used for oxidative phosphorylation.

Full Answer

What is the electron transport chain and how does it work?

Apr 12, 2020 · a. Which two compounds donate their electrons to the electron transport chain? Pick both. CO2, NADH, O2, NAD+, GTP, FADH2 b. Which molecule is the final electron acceptor of the electron transport chain? CO2, NADH, O2 NAD+, GTP, FADH2.

What is the role of hydrogen ions in the electron transport chain?

The reduced coenzymes generated by the citric acid cycle donate electrons in a series of reactions called the electron transport chain. The energy from the electron transport chain is used for oxidative phosphorylation. For each part, select all that apply. (a) Which compounds donate electrons to the electron transport chain? 1. H2O. 2. NADH. 3. NAD+. 4. ATP. 5. ADP. 6. O2. 7. …

What is the final acceptor of electrons in electron transport chain?

Jun 05, 2012 · The reduced NAD and FAD donate the electrons of the hydrogen atoms they are carrying to the first molecule in the electron transport chain.

How does the electron transport chain generate an electrochemical gradient?

Dec 09, 2021 · Which compounds donate electrons to the electron transport chain? NADH and FADH2 are both electron carriers that donate their electrons to the electron transport chain . The electrons ultimately reduce O2 to water in the final step of electron transport.

What Product Is Made By The Electron Transport Chain?

The end products of the electron transport chain are water and ATP. A number of intermediate compounds of the citric acid cycle can be diverted into the anabolism of other biochemical molecules, such as nonessential amino acids, sugars, and lipids.

What are the products of the electron transport chain quizlet?

Once ATP is created, the waste products of the electron transport chain are the hydrogen ions and the electrons.

What is a product of the electron transport chain started by photosystem II?

Photosystem II produces. both oxygen and high-energy electrons. Photosystem I initiates the electron transport chain that produces. NADPH.

What is the final product of the electron transport chain quizlet?

H2O (water) is formed as a final product of the electron transport chain.

What occurs in the electron transport chain?

In the electron transport chain, electrons are passed from one molecule to another, and energy released in these electron transfers is used to form an electrochemical gradient. In chemiosmosis, the energy stored in the gradient is used to make ATP.

What are the products of the electron transport chain in the second stage of cellular respiration?

The second stage of cellular respiration is the transfer of the energy in pyruvate, which is the energy initially in glucose, into two energy carriers, NADH and FADH2. A small amount of ATP is also made during this process. This process occurs in a continuous cycle, named after its discover, Hans Krebs.

What is FeS in electron transport chain?

It is an additional component found in the electron transport chain. It is also called FeS or none-haeme iron. It consists of a cluster of cysteine residues which complex iron through covalent bonds with the sulfur of cysteine. It is associated with the flavoproteins and cytochrome b.

How does the electron transport chain work?

Energy obtained through the transfer of electrons down the electron transport chain is used to pump protons from the mitochondrial matrix into the intermembrane space , creating an electrochemical proton gradient ( ΔpH) across the inner mitochondrial membrane. This proton gradient is largely but not exclusively responsible for the mitochondrial membrane potential (ΔΨ M ). It allows ATP synthase to use the flow of H + through the enzyme back into the matrix to generate ATP from adenosine diphosphate (ADP) and inorganic phosphate. Complex I (NADH coenzyme Q reductase; labeled I) accepts electrons from the Krebs cycle electron carrier nicotinamide adenine dinucleotide (NADH), and passes them to coenzyme Q (ubiquinone; labeled Q), which also receives electrons from complex II ( succinate dehydrogenase; labeled II). Q passes electrons to complex III ( cytochrome bc 1 complex; labeled III), which passes them to cytochrome c (cyt c ). Cyt c passes electrons to complex IV ( cytochrome c oxidase; labeled IV), which uses the electrons and hydrogen ions to reduce molecular oxygen to water.

What is the photosynthesis electron transport chain?

Photosynthetic electron transport chains, like the mitochondrial chain, can be considered as a special case of the bacterial systems. They use mobile, lipid-soluble quinone carriers ( phylloquinone and plastoquinone) and mobile, water-soluble carriers ( cytochromes, electron transport chain.).

Why is oxygen used as an electron acceptor?

In aerobic bacteria and facultative anaerobes if oxygen is available, it is invariably used as the terminal electron acceptor, because it generates the greatest Gibbs free energy change and produces the most energy.

What is the final electron acceptor in aerobic respiration?

In aerobic respiration, the flow of electrons terminates with molecular oxygen being the final electron acceptor. In anaerobic respiration, other electron acceptors are used, such as sulfate . In the electron transport chain, the redox reactions are driven by the Gibbs free energy state of the components.

Which cell produces ATP?

Most eukaryotic cells have mitochondria, which produce ATP from products of the citric acid cycle, fatty acid oxidation, and amino acid oxidation. At the inner mitochondrial membrane, electrons from NADH and FADH 2 pass through the electron transport chain to oxygen, which is reduced to water.

What is Gibbs free energy?

Gibbs free energy is related to a quantity called the redox potential. The complexes in the electron transport chain harvest the energy of the redox reactions that occur when transferring electrons from a low redox potential to a higher redox potential, creating an electrochemical gradient. It is the electrochemical gradient created ...

How is oxidative phosphorylation done?

In oxidative phosphorylation, electrons are transferred from a low-energy electron donor such as NADH to an acceptor such as O 2) through an electron transport chain. In photophosphorylation, the energy of sunlight is used to create a high-energy electron donor which can subsequently reduce redox active components. These components are then coupled to ATP synthesis via proton translocation by the electron transport chain.

What happens to electrons in the electron transport chain?

The electrons passing through the electron transport chain gradually lose energy, High-energy electrons donated to the chain by either NADH or FADH 2 complete the chain, as low-energy electrons reduce oxygen molecules and form water.

Where is the electron transport chain located?

The electron transport chain is present in multiple copies in the inner mitochondrial membrane of eukaryotes and the plasma membrane of prokaryotes. Note, however, that the electron transport chain of prokaryotes may not require oxygen as some live in anaerobic conditions. The common feature of all electron transport chains is the presence ...

What is FMN in biology?

FMN, which is derived from vitamin B 2 , also called riboflavin, is one of several prosthetic groups or co-factors in the electron transport chain . A prosthetic group is a non-protein molecule required for the activity of a protein. Prosthetic groups are organic or inorganic, non-peptide molecules bound to a protein that facilitate its function;

What are the pathways of cellular respiration?

You have just read about two pathways in cellular respiration—glycolysis and the citric acid cycle —that generate ATP. However, most of the ATP generated during the aerobic catabolism of glucose is not generated directly ...

How does a concentration gradient form?

Therefore, a concentration gradient forms in which hydrogen ions diffuse out of the matrix space by passing through ATP synthase. The current of hydrogen ions powers the catalytic action of ATP synthase, which phosphorylates ADP, producing ATP. Figure 1.

Which part of the aerobic respiration system uses atmospheric oxygen?

The electron transport chain (Figure 1) is the last component of aerobic respiration and is the only part of glucose metabolism that uses atmospheric oxygen. Oxygen continuously diffuses into plants; in animals, it enters the body through the respiratory system.

What is the process of electron transport?

Electron transport is a series of redox reactions that resemble a relay race or bucket brigade in that electrons are passed rapidly from one component to the next, to the endpoint of the chain where the electrons reduce molecular oxygen, producing water.

What is the electron transport chain?

The electron transport chain involves a series of redox reactions that relies on protein complexes to transfer electrons from a donor molecule to an acceptor molecule. As a result of these reactions, the proton gradient is produced, enabling mechanical work to be converted into chemical energy, allowing ATP synthesis.

How do electrons move in the electron transfer chain?

In the electron transfer chain, electrons move along a series of proteins to generate an expulsion type force to move hydrogen ions, or protons, across the mitochondrial membrane. The electrons begin their reactions in Complex I, continuing onto Complex II, traversed to Complex III and cytochrome c via coenzyme Q, and then finally to Complex IV. The complexes themselves are complex-structured proteins embedded in the phospholipid membrane. They are combined with a metal ion, such as iron, to help with proton expulsion into the intermembrane space as well as other functions. The complexes also undergo conformational changes to allow openings for the transmembrane movement of protons.

What is the mechanism that drives ATP synthesis?

Often, the use of a proton gradient is referred to as the chemiosmotic mechanism that drives ATP synthesis since it relies on a higher concentration of protons to generate “proton motive force”. The amount of ATP created is directly proportional to the number of protons that are pumped across the inner mitochondrial membrane. ...

What is the electron transport chain?

The electron transport chain is also called the Cytochrome oxidase system or as the Respiratory chain. The components of the chain include FMN, Fe–S centers, coenzyme Q, and a series of cytochromes (b, c1, c, and aa3). The energy derived from the transfer of electrons through the electron transport chain is used to pump protons across ...

How does ATP produce electrons?

The production of ATP is coupled to the transfer of electrons through the electron transport chain to O2. The overall process is known as oxidative phosphorylation. Protons flow down their electrochemical gradient through the membrane-bound ATP synthase. The flow of protons through the ATPase allows the enzyme to synthesize ATP.

How is ATP produced?

ATP is generated as a result of the energy produced when electrons from NADH and FADH2 are passed to molecular oxygen by a series of electron carriers, collectively known as the electron transport chain ( ETC). The electron transport chain is also called the Cytochrome oxidase system or as the Respiratory chain.

Where is the respiratory chain located?

Location of ETC. The respiratory chain is located in the cytoplasmic membrane of bacteria but in case of eukaryotic cells it is located on the membrane of mitochondria.

What is the final step of cellular respiration?

The electron transport chain is the final and most important step of cellular respiration. While Glycolysis and the Citric Acid Cycle make the necessary precursors, the electron transport chain is where a majority of the ATP is created. It has an important role in both photosynthesis and cellular respiration.

Why are NADH and FADH2 energy rich?

The NADH and FADH2 formed in glycolysis, TCA cycle and fatty acid oxidation are energy-rich molecules because they contain a pair of electrons that have high transfer potential.

Overview

Mitochondrial electron transport chains

Bacterial electron transport chains

Photosynthetic

See also

Further reading

External links