During the reduction of oxygen to water, reactive oxygen species such as superoxide or hydrogen peroxide can be produced. These molecules are highly reactive and such can react with proteins or DNA to cause cellular damage or mutations.
These molecules "drop off" electrons to the complexes in the electron transport chain. A culture of cells is grown on a special medium containing substance "Y". Substance "Y" is a poison that blocks the electron transport chain. The addition of substance "Y" to the culture of cells will likely result in which of the following?
The ATP is produced by a proton gradient made as electrons are transported throughout the chain. Inhibition of this process by "Substance Y" will block the formation of a proton gradient.
Blocking the proton gradient will not allow for oxidative phosphorylation to occur, thus greatly decreasing the amount of ATP produced. Oxygen is the final electron acceptor of electrons as they are passed down the electron chain.
The electrons move and combine with oxygen to produce. Water and hydrogen are just byproducts of the acceptance of the electron, not the acceptor. The electrons are actually brought to the electron transport chain by carries like and. This answer involves a careful examination of respiration processes. FADH2 is directly attached onto the second protein of the electron transport chain and therefore the electrons of FADH2 electron carrier are dropped off at the second protein not the first.
The movement of the electrons through the electron transport chain also does not create energy directly, but does create a proton gradient that is later used to create energy. The movement of protons down its proton gradient through ATP synthase does, however, generate energy.
It actually generates around 30 ATP molecules per one glucose. If you've found an issue with this question, please let us know. With the help of the community we can continue to improve our educational resources. If Varsity Tutors takes action in response to an Infringement Notice, it will make a good faith attempt to contact the party that made such content available by means of the most recent email address, if any, provided by such party to Varsity Tutors.
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Hanley Rd, Suite St. Four protons are needed to synthesize 1 ATP. Since a single NADH produces 2. Importantly, glycolysis occurs in the cytosol and the ETC is located in the mitochondria in eukaryotes.
The mitochondrial membrane is not permeable to NADH, hence the electrons of the 2 NADH that are produced by glycolysis need to be shuttled into the mitochondria. Given the different ATP yield depending on the electron carrier, the total yield of cellular respiration is 30 to 32 ATP per glucose molecule.
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If you have any questions, please do not hesitate to reach out to our customer success team. Login processing Chapter 8: Cellular Respiration. Chapter 1: Scientific Inquiry. Chapter 2: Chemistry of Life.
Chapter 3: Macromolecules. Chapter 4: Cell Structure and Function. Chapter 5: Membranes and Cellular Transport. Chapter 6: Cell Signaling. Chapter 7: Metabolism. The name of this metabolic pathway is derived from citric acid, a type of tricarboxylic acid that is first consumed and then regenerated by this sequence of reactions to complete the cycle.
The net result of these two closely linked pathways is the oxidation of nutrients to produce usable energy in the form of ATP. Components of the TCA cycle were derived from anaerobic bacteria, and the TCA cycle itself may have evolved more than once. Theoretically there are several alternatives to the TCA cycle, however the TCA cycle appears to be the most efficient. If several alternatives independently evolved, they all rapidly converged to the TCA cycle.
Through the catabolism of sugars, fats, and proteins, a two carbon organic product acetate in the form of acetyl-CoA is produced. One of the primary sources of acetyl-CoA is sugars that are broken down by glycolysis to produce pyruvate that, in turn, is decarboxylated by the enzyme pyruvate dehydrogenase.
This generates acetyl-CoA according to the following reaction scheme:. Privacy Policy. Skip to main content. Microbial Metabolism. Search for:.
The Citric Acid Krebs Cycle. Learning Objectives List the steps of the Krebs or citric acid cycle. Key Takeaways Key Points The four-carbon molecule, oxaloacetate, that began the cycle is regenerated after the eight steps of the citric acid cycle. The eight steps of the citric acid cycle are a series of redox, dehydration, hydration, and decarboxylation reactions. Breakdown of Pyruvate After glycolysis, pyruvate is converted into acetyl CoA in order to enter the citric acid cycle.
Learning Objectives Explain why cells break down pyruvate. Key Takeaways Key Points In the conversion of pyruvate to acetyl CoA, each pyruvate molecule loses one carbon atom with the release of carbon dioxide. In the final step of the breakdown of pyruvate, an acetyl group is transferred to Coenzyme A to produce acetyl CoA. Key Terms acetyl CoA : a molecule that conveys the carbon atoms from glycolysis pyruvate to the citric acid cycle to be oxidized for energy production.
Life is possible only if molecules and cells remain organized. Organization requires energy, as governed by the laws of thermodynamics. Just about anything a living organism does requires energy. We most often think of energy as food or calories. Cells, however, think of energy as ATP. Cellular respiration is the process of taking the food we eat like sugar and converting it into an energy that can be used by cells - ATP. The breakdown of energy rich molecules like glucose to obtain energy is called cellular respiration.
Cellular respiration occurs in both plants and animals. The energy gained from the breakdown of glucose is stored in cells as ATP. Cellular respiration can be summarized by the following equation:.
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