Describe how fats and proteins are brought into the Krebs cycle?
Fats are broken down by beta oxidation into molecules of acetyl-CoA. More specifically, since fats are normally contain an even number of carbon atoms (n), the number of aceteyl-CoA molecule produced from one fat is (n/2) since acetyl-CoA is a 2 carbon molecule. Acetyl-CoA is then funneled in to the Krebs cycle just like the products of glycolysis: by combination with oxaloacetate to form citric acid Amino acids (of proteins) are a little more complicated. All amino acids can be broken down into acetyl-CoA and enter in the way previously described. However, many amino acids can be converted into actual intermediates of the Krebs cycle. For example, glutamate can be directly converted to alpha ketoglutarate, one of the kep components of the cycle.
What is another name for the Krebs cycle?
Citric acid cycle cause citrous is the first product of the cycle.
Where does the Krebs cycle occur? How does it occur?
The Krebs cycle occurs in the mitochondria of all eukaryotic cells that have mitochondria (i.e. not red blood cells). The Krebs cycle is also referred to as the citric acid cycle and more properly as the tricarboxylic acid cycle.I would refer you to this figure: Citric acid cycle - Wikipedia for the chemical details of the cycle.TCA is the process by which Acetyl-CoA is oxidized to CO2. The story of how those oxidizing agents are recycled is the story of the mitochondrial electron transport chain that encompasses the mitochondrial complexes I-IV (See Electron transport chain - Wikipedia for more details). The purpose of the electron transport chain is to create a proton gradient across the inner mitochondrial membrane. The energy derived from both of these processes is actualized by mitochondrial complex V, the so-called F0-F1 ATPase, that synthesizes ATP from ADP and Phosphate by a process called conformational catalysis (see ATP synthase - Wikipedia for more details). ATP is the energy currency of the cell because it is possible to couple the hydrolysis of its phosphoryl groups to reactions that are otherwise unfavorable (i.e. do chemical work). Wikipedia and numerous textbooks describe these processes in great detail, but this is the big picture. Catabolism is “burning” food (largely carbohydrates and fats) to supply the cell with energy so that the cell can perform the biochemical reactions associated with living. Krebs cycle is just one part of this process.I hope this helps
What is the Krebs cycle? Where does it occur?
The second stage of aerobic respiration is theKrebs cycle, which occurs within the matrix of the mitochondriaThe Krebs cycle is also commonly referred to as the citric acid cycle or the tricarboxylic acid (TCA) cycleIn the Krebs cycle, acetyl CoA transfers its acetyl group to a 4C compound (oxaloacetate) to make a 6C compound (citrate)Coenzyme A is released and can return to the link reaction to form another molecule of acetyl CoAOver a series of reactions, the 6C compound is broken down to reform the original 4C compound (hence, a cycle)Two carbon atoms are released via decarboxylation to form two molecules of carbon dioxide (CO2)Multiple oxidation reactions result in the reduction of hydrogen carriers (3 × NADH + H+ ; 1 × FADH2)One molecule of ATP is produced directly via substrate level phosphorylationAs the link reaction produces two molecules of acetyl CoA (one per each pyruvate), the Krebs cycle occurs twicePer glucose molecule, the Krebs cycle produces: 4 × CO2 ; 2 × ATP ; 6 × NADH + H+ ; 2 × FADH2The Krebs CycleYou can visit www.internetpadhai.com for more video tutorial related to various subjects like physics or maths or chemistry,etc and different topics.
What is Krebs Cycle? The Citric Acid Cycle?
The Krebs cycle refers to a complex series of chemical reactions in all cells that utilize oxygen as part of their respiration process. This includes those cells of creatures from the higher animal kingdom, such as humans. The Krebs cycle produces carbon dioxide and a compound rich in energy, Adenosine triphosphate (ATP). This chemical provides cells with the energy required for the synthesis of proteins from amino acids and the replication of deoxyribonucleic acid (DNA). The Krebs cycle, also known as the tricarboxylic acid cycle (TCA), was first recognized in 1937 by the man for whom it is named, German biochemist Hans Adolph Krebs. His highly detailed and extensive research in the field of cellular metabolism and other scientific endeavors gleaned him the Nobel Prize for Physiology or Medicine in 1953. In short, the Krebs cycle constitutes the discovery of the major source of energy in all living organisms. Within the Krebs cycle, energy in the form of ATP is usually derived from the breakdown of glucose, although fats and proteins can also be utilized as energy sources. Since glucose can pass through cell membranes, it transports energy from one part of the body to another. The Krebs cycle affects all types of life and is, as such, the metabolic pathway within the cells. This pathway chemically converts carbohydrates, fats, and proteins into carbon dioxide, and converts water into serviceable energy. The Krebs cycle is involved in the second of three major stages every living cell must undergo in order to produce energy, which it needs in order to survive. The enzymes that cause each step of the process to occur are all located in the cell's "power plant." In animals, this is the mitochondria; in plants, it is the chloroplasts; and in microorganisms, it can be found in the cell membrane. The Krebs cycle is also known as the citric acid cycle, because citric acid is the very first product generated by this sequence of chemical conversions.
Krebs Cycle/Citric Acid Cycle... poem or story....?
The citric acid cycle begins with acetyl-CoA transferring its two-carbon acetyl group to the four-carbon acceptor compound (oxaloacetate) to form a six-carbon compound (citrate). The citrate then goes through a series of chemical transformations, losing first one, then a second carboxyl group as CO2. The carbons lost as CO2 originate from what was oxaloacetate, not directly from acetyl-CoA. The carbons donated by acetyl-CoA become part of the oxaloacetate carbon backbone after the first turn of the citric acid cycle. Loss of the acetyl-CoA-donated carbons as CO2 requires several turns of the citric acid cycle. However, because of the role of the citric acid cycle in anabolism, they may not be lost since many TCA cycle intermediates are also used as precursors for the biosynthesis of other molecules. Most of the energy made available by the oxidative steps of the cycle is transferred as energy-rich electrons to NAD+, forming NADH. For each acetyl group that enters the citric acid cycle, three molecules of NADH are produced. Electrons are also transferred to the electron acceptor Q, forming QH2. At the end of each cycle, the four-carbon oxaloacetate has been regenerated, and the cycle continues.
Describe the cellular regions where glycolysis, the Krebs cycle, and the electron transport chain occur.?
Glycolysis occurs in the cytosal, as well as fermentation. Kreb's Cycle occurs in the matrix of the mitochondria, and the ETC is on the inner mitochondral membrane.
How can the Krebs cycle be summarized?
The Krebs Cycle is typically known as the “Citric Acid Cycle”, a secondary step in cellular respiration. I find it important to understand how the Kreb’s Cycle (Citric Acid Cycle) is driven by it’s other intermediate reactions in cellular respiration, which is:Glycolysis - this is the first stage of cellular respiration, that does not require oxygen (anaerobic) which occurs in the cytoplasm, this process breaks down “lysis” glucose “glyc(o)” into 2 molecules of pyruvate (a 3-carbon compound). Since glucose is 6 carbon, breaking it down into two 3-carbons is much more efficient.Glycolysis requires 1 glucose molecule and 2 ATPGlycolysis produces 2 pyruvate molecules, 4 ATP, 2 NADH. *If you were following along, we used 2 ATP to drive the decomposition of glucose, and thus we really only produce a net of 2 ATP.Now we can transition to the Krebs Cycle (Citric Acid Cycle) by using 2 pyruvate, 2 CoA, and 2 NAD+, to produce 2 Acetyl Coa, 2 NADH + H+, and 2 CO2 molecules. This is an important process because it releases CO2. We cross the 1st membrane of the mitochondria, passes through the inter-membrane spaces past the second membrane and into the mitochondrial matrix.Kreb’s Cycle - this is the third stage of cellular respiration that occurs in the matrix of the mitochondria. During Krebs cycle both NAD + & FAD are reduced to NADH & FADH2 respectively. In this process, we use 2 Acetyl CoA (produced in the transitional stage), 2 ADP, 2 inorganic phosphates (which will later phosphorylate to create ATP), 6 NAD+, 2 FAD, and produce 2 ATP, 6 NADH, 2 FADH2, and 4 CO2 molecules. For every Acetyl CoA that enters the Krebs cycle, the cycle turns once. For every glucose molecule that starts cell respiration, 2 pyruvates are formed, forming 2 acetyl CoAs, thus turning the Krebs cycle twice. FAD is flavin adenine dinucleotide, a coenzyme necessary for the reaction as well as an electron donor in the electron transport chain The aforementioned Acetyl CoA molecules (with oxaloacetate) are used to further drive the Citric Acid cycle. The byproducts of this is H2O and CO2, and make small amounts of ATP