Concept explainers
(a)
Interpretation:
Whether the compound acyl CoA is associated with (1) the β-oxidation pathway, (2) ketogenesis, (3) both the β-oxidation pathway and ketogenesis has to be determined.
Concept introduction:
Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules.
The β-oxidation is a catabolic process occurring in the body through which, fatty acid molecules are broken down in the mitochondria of the cells to generate energy. The process involves breaking down long fatty acid chains that have been converted to acyl CoA chains into smaller fatty acyl CoA chains. The fatty acid chain is broken down until the final acyl CoA chain cannot be broken down any further. The end products of this
(b)
Interpretation:
Whether the compound enoyl CoA is associated with (1) the β-oxidation pathway, (2) ketogenesis, (3) both the β-oxidation pathway and ketogenesis has to be determined.
Concept introduction:
Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketone bodies are generally produced when the amount of acetyl CoA in the body is much larger than the amount of oxaloacetate. This happens due to the carbohydrate-lipid imbalance in the body caused by much smaller intake of food rich in carbohydrates, or inefficient processing of glucose by the body.
The β-oxidation is a catabolic process occurring in the body through which, fatty acid molecules are broken down in the mitochondria of the cells to generate energy. The process involves breaking down long fatty acid chains that have been converted to acyl CoA chains into smaller fatty acyl CoA chains. The fatty acid chain is broken down until the final acyl CoA chain cannot be broken down any further. The end products of this metabolic process are acetyl CoA, FADH2 and NADH. These three molecules later enter the Krebs cycle where they are used to produce ATP molecules.
(c)
Interpretation:
Whether the compound acetyl CoA is associated with (1) the β-oxidation pathway, (2) ketogenesis, (3) both the β-oxidation pathway and ketogenesis has to be determined.
Concept introduction:
Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketone bodies are generally produced when the amount of acetyl CoA in the body is much larger than the amount of oxaloacetate. This happens due to the carbohydrate-lipid imbalance in the body caused by much smaller intake of food rich in carbohydrates, or inefficient processing of glucose by the body.
The β-oxidation is a catabolic process occurring in the body through which, fatty acid molecules are broken down in the mitochondria of the cells to generate energy. The process involves breaking down long fatty acid chains that have been converted to acyl CoA chains into smaller fatty acyl CoA chains. The fatty acid chain is broken down until the final acyl CoA chain cannot be broken down any further. The end products of this metabolic process are acetyl CoA, FADH2 and NADH. These three molecules later enter the Krebs cycle where they are used to produce ATP molecules.
(d)
Interpretation:
Whether the compound β-hydroxybutyrate is associated with (1) the β-oxidation pathway, (2) ketogenesis, (3) both the β-oxidation pathway and ketogenesis has to be determined.
Concept introduction:
Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketone bodies are generally produced when the amount of acetyl CoA in the body is much larger than the amount of oxaloacetate. This happens due to the carbohydrate-lipid imbalance in the body caused by much smaller intake of food rich in carbohydrates, or inefficient processing of glucose by the body.
The β-oxidation is a catabolic process occurring in the body through which, fatty acid molecules are broken down in the mitochondria of the cells to generate energy. The process involves breaking down long fatty acid chains that have been converted to acyl CoA chains into smaller fatty acyl CoA chains. The fatty acid chain is broken down until the final acyl CoA chain cannot be broken down any further. The end products of this metabolic process are acetyl CoA, FADH2 and NADH. These three molecules later enter the Krebs cycle where they are used to produce ATP molecules.
Want to see the full answer?
Check out a sample textbook solutionChapter 25 Solutions
EBK GENERAL, ORGANIC, AND BIOLOGICAL CH
- Consider the docosanoic acid, C21H43CO2H a. Label the a and B carbons b. Draw the acyl CoA derived from this fatty acid c. How many acetyl CoA molecules are formed by complete B-oxidation? d. How many cycles of B-oxidation are needed for complete oxidation? e. How many molecules of ATP are formed from the complete catabolism of this fatty acid?arrow_forwardCompare and contrast the following items related to lipid metabolism. Cite their main similarities/or differences. 1. Dehydrogenase enzyme vs. dehydratase enzyme(in context of lipid metabolism). 2. Steroid hormones vs. prostaglandins (in terms of their biosynthetic pathways). 3. Fatty acid synthase complex vs. pyruvate dehydrogenase complex.arrow_forwardThe sources of the three (3) carbons in malonyl-Coa is/are: a. 1 C from C02 and 2 C from acetyl-CoA b. 1 C from HCO3- and 2 C from acetyl-CoA c. 1 C from biotin and 2 C from acetyl-CoA d. All three C from acetyl-CoAarrow_forward
- Which of the following reactions correspond to the decarboxylation step during ketone body formation? A. 2 acetyl-CoA → acetoacetyl-CoA B. ß-hydroxybutarate → acetoacetate C. Acetoacetate → acetone D. HMG-CoA → mevalonatearrow_forwardCompare and contrast the following items related to lipid metabolism. Cite their main similarities/or differences. 1. Steroid hormones vs. prostaglandins (in terms of their biosynthetic pathways). 2. Fatty acid synthase complex vs. pyruvate dehydrogenase complex.arrow_forward(8) B-ketothiolase is a multifunctional enzyme in lipid catabolism. Which of the following is NOT one of its functions? (A) It catalyzes the release of (2) acetyl CoA from acetoacetyl CoA during ketolysis. (B) It removes an acetyl CoA from the fatty acyl chain during B-oxidation. (C) It forms acetoacetate by removing acetyl CoA from HMG CoA during ketogenesis. (D) It condenses (2) acetyl CoA molecules to form acetoacetyl CoA during ketogenesis. (9) What is HMG-COA, in the context of fatty acid catabolism? (A) a product of fatty acid oxidation (B) a ketone body made in liver cells (C) a 6-carbon precursor to the acetoacetate ketone body (D) a 4-carbon precursor to the acetoacetate ketone body (E) a product formed when the B-hydroxybutyrate ketone body is oxidized in brain cells (10) Which of the following symptoms might you expect to see in a patient with defective acyl CoA dehydrogenase under fasting conditions? (A) slowed gluconeogenesis in liver (B) hypoglycemia (C) elevated glycogen…arrow_forward
- Acetyl-CoA carboxylase is inhibited by A. biotin B. citrate C. acetyl-CoA D. palmitatearrow_forwardIdentify the CORRECT statements regarding Ketones. SELECT ALL THAT APPLY A. Ketones are synthesized from excess pyruvate B. Ketones may be oxidized to yield cellular energy C. Ketogensis involves removal of coA (s-coa) groups D. Insulin promotes ketogenesisarrow_forwardIndicate what will happen ( increase, decrease or no effect) tothe activity of the enzyme or rate of the metabolic pathway in the given conditions a. release of glucagon in the blood to the activity of carnitine acyl transferase 1 b. high malonyl CoA to the activity of carnitine acyl transferase I C. Epinephrine to the activity og glycogen synthase d. high citrate to the activity of acetyl CoA carboxylase e. high acetyl CoA to ketogenesisarrow_forward
- Please explain the role of pantothenic acid-derived CoA as a carrier of acetyl group in carbohydrate metabolism.arrow_forwardCompare and contrast the following items related to lipid metabolism. Cite their main similarities/or differences. 1.lysophosphatidylcholine vs. phosphatidylethanolamine 2.trimyristin vs. triolein. 3. ACP vs. carnitine-acyl transferase.arrow_forwardIn the metabolism of lipids, B-oxidation will yield (n/2) acetyl-CoA fragments from a C fatty acid. Fatty acids with an odd number of carbons are also metabolized by B-oxidation to acetyl-CoA fragments. However, the final fragment is a. propionyl-COA O b. succinyl-CoA O c. Oxaloacetate O d malonyl-COA O e glyceraldehyde-3-phosphatearrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education