Place the following steps of the citric acid cycle in order: Pyruvate is converted to Acetyl-CoA ($$+CO_2$$, NADH). 1 Malate is converted into oxaloacetate ($$+NADH$$). 2 Acetyl-CoA is attached to oxaloacetate to make citrate (rate-limiting step). 3 Fumarate is converted into malate using $$H_2O$$. 4 $$\alpha$$-ketoglutarate undergoes oxidative decarboxylation to succinyl-CoA ($$+CO_2$$, $$+NADH$$). 5 Succinate is oxidized to fumarate ($$+FADH_2$$). 6 Citrate is isomerized to isocitrate. 7 Succinyl-CoA undergoes substrate-level phosphorylation to succinate ($$+GTP$$). 8 Isocitrate undergoes oxidative decarboxylation to form $$\alpha$$-ketoglutarate ($$+CO_2$$, $$+NADH$$).
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The citric acid cycle begins with the condensation of Acetyl-CoA and oxaloacetate. Step 2: Acetyl-CoA is attached to oxaloacetate to make citrate (rate-limiting step). Next, citrate undergoes isomerization. Step 6: Citrate is isomerized to Show more…
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The citric acid cycle takes place in mitochondria. It is also known as the Krebs cycle or the tricarboxylic acid cycle. The transformation of citrate to isocitrate is the first step of the cycle. This step is catalyzed by the enzyme aconitase. The next step is the conversion of isocitrate to alpha-ketoglutarate, which is catalyzed by the enzyme isocitrate dehydrogenase. This step produces NADH and releases carbon dioxide. The next step is the conversion of alpha-ketoglutarate to succinyl-CoA, which is catalyzed by the enzyme alpha-ketoglutarate dehydrogenase. This step also produces NADH and releases carbon dioxide. The next step is the conversion of succinyl-CoA to succinate, which is catalyzed by the enzyme succinyl-CoA synthetase. This step produces GTP or ATP. The next step is the conversion of succinate to fumarate, which is catalyzed by the enzyme succinate dehydrogenase. This step produces FADH2. The final step is the conversion of fumarate to malate, which is catalyzed by the enzyme fumarase. This step involves hydration. The cycle then starts again with the conversion of malate back to citrate.
Adi S.
The Krebs Cycle includes all of the 7 steps. The first step is the conversion of Pyruvic Acid (C3H4O3) to Acetyl CoA (C2H3O2). The second step is the conversion of Acetyl CoA to Citric Acid (C6H8O7). The third step is the conversion of Citric Acid to Isocitric Acid (C6H8O7). The fourth step is the conversion of Isocitric Acid to α-Ketoglutaric Acid (C5H6O5). The fifth step is the conversion of α-Ketoglutaric Acid to Succinyl CoA (C4H6O4). The sixth step is the conversion of Succinyl CoA to Succinic Acid (C4H6O4). The seventh step is the conversion of Succinic Acid to Fumaric Acid (C4H4O4). In each mole of glucose that enters glycolysis, 7 moles of ATP, 7 moles of NADH, and 2 moles of FADH2 are produced. The correct sequence of the Krebs Cycle is as follows: Glycolysis, Pyruvate Decarboxylation, Krebs Cycle, Electron Transport System (ETS) + Chemiosmosis.
Sri K.
The Krebs cycle, also known as the citric acid cycle or the tricarboxylic acid cycle, is a series of chemical reactions that occur in the mitochondria of cells. It is an essential part of cellular respiration, which is the process by which cells generate energy. The main steps of the Krebs cycle are as follows: 1. Acetyl-CoA Formation: The cycle begins with the formation of acetyl-CoA, which is derived from the breakdown of carbohydrates, fats, and proteins. Acetyl-CoA enters the cycle by combining with a four-carbon molecule called oxaloacetate, forming a six-carbon molecule called citrate. 2. Citrate Isomerization: Citrate is then converted into its isomer, isocitrate, through a series of enzymatic reactions. 3. Oxidative Decarboxylation: Isocitrate is further converted into alpha-ketoglutarate, releasing carbon dioxide and generating NADH, a molecule that carries high-energy electrons. 4. Alpha-Ketoglutarate Decarboxylation: Alpha-ketoglutarate is converted into succinyl-CoA, releasing another molecule of carbon dioxide and generating NADH. 5. Succinyl-CoA Conversion: Succinyl-CoA is then converted into succinate, generating a molecule of GTP, which can be used to produce ATP, the cell's main energy source. 6. Succinate Oxidation: Succinate is converted into fumarate, generating FADH2, another molecule that carries high-energy electrons. 7. Fumarate Hydration: Fumarate is hydrated to form malate. 8. Malate Oxidation: Malate is oxidized to form oxaloacetate, generating NADH. The overall result of the Krebs cycle is the complete oxidation of acetyl-CoA, releasing high-energy electrons that are carried by NADH and FADH2. These electrons are then used in the electron transport chain to generate ATP, the energy currency of the cell.
Keemin L.
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