12. Free oxidation, oxidative and substrate phosphorylation. 13. Stages of high energy compound production in the electron transport chain. The ratio P/O. 800 14. Regulation of oxidative phosphorylation. The respiratory control. The role of some biologically active and medicinal substances. 15. Uncoupling of ATP synthesis from electron transport. Ther- moregulative function of tissue respiration. 16. The structure of mitochondria. Selective permeability of the mi- tochondrial membrane for substrata, ADP and ATP. Bot 17. Infringements of an energetic metabolism as result of hypoxia. Hypoxic conditions. 00 18. Vitamins B₂ and niacin, ubiquinone. Their role in biological oxi- dation. 19. Cytochrome P450 monooxygenase system. Oxidation in the pe- roxisome. Tocopherol, ascorbic acid and ß-carotene as antioxidant chemicals. A slovil 20. The tricarboxylic acid cycle: biological role, sequence of reac- tions. goloin 21 The allosteric mechanisms of the TCA cycle regulation. 22. Integration of common pathways of catabolism with the electron transport chain (on example of TCA cycle).
Ответы
Free oxidation refers to the process of oxidizing organic compounds in the absence of an external electron acceptor, resulting in the production of carbon dioxide and water. Oxidative phosphorylation is the process by which energy released from the electron transport chain is used to generate ATP. Substrate phosphorylation refers to the process by which ATP is generated directly from the phosphorylation of ADP using energy released from the breakdown of a substrate molecule.
The stages of high energy compound production in the electron transport chain include the oxidation of NADH and FADH2, the transfer of electrons through the electron transport chain, and the production of a proton gradient across the inner mitochondrial membrane. The P/O ratio refers to the number of ATP molecules produced per molecule of oxygen consumed during oxidative phosphorylation.
The regulation of oxidative phosphorylation is accomplished through the respiratory control mechanism, which adjusts the rate of electron transport to match the rate of ATP synthesis. Biologically active and medicinal substances such as uncoupling agents and inhibitors can also modulate the rate of oxidative phosphorylation.
Uncoupling of ATP synthesis from electron transport can occur through the action of uncoupling proteins, which allow protons to leak across the mitochondrial membrane and dissipate the proton gradient. This process can generate heat and is important for thermoregulation in some tissues.
Mitochondria have a double membrane structure with selective permeability for substrates, ADP, and ATP. The outer membrane is permeable to small molecules, while the inner membrane is highly impermeable and contains transporters for metabolites and proteins.
Hypoxia can lead to disruptions in energy metabolism, as a reduced supply of oxygen can impair oxidative phosphorylation and result in the accumulation of metabolic intermediates. Hypoxic conditions can arise from a variety of causes, including high altitude, lung disease, and heart failure.
Vitamins B2 and niacin, along with ubiquinone, play important roles in biological oxidation by serving as cofactors for enzymes involved in the electron transport chain.
The cytochrome P450 monooxygenase system is a group of enzymes involved in the oxidation of xenobiotics and endogenous compounds. Oxidation can also occur in the peroxisome, where reactive oxygen species are produced and detoxified by catalase. Antioxidant chemicals such as tocopherol, ascorbic acid, and beta-carotene can help prevent oxidative damage.
The tricarboxylic acid (TCA) cycle, also known as the Krebs cycle, is a series of enzyme-catalyzed reactions that play a central role in the catabolism of carbohydrates, fats, and amino acids. The cycle generates ATP and reducing equivalents in the form of NADH and FADH2.
The TCA cycle is regulated by a variety of allosteric mechanisms, including the inhibition of key enzymes by ATP and NADH and the activation of enzymes by ADP and calcium ions.
The TCA cycle is integrated with the electron transport chain through the production of NADH and FADH2, which serve as electron donors for the electron transport chain. The energy generated by the electron transport chain is used to drive ATP synthesis via oxidative phosphorylation.