Reactants and Products of Lipid Catabolism - Biochemistry
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How many rounds of beta oxidation will a fatty acid with a hydrocarbon tail that is 20 carbons long undergo? What are the products?
How many rounds of beta oxidation will a fatty acid with a hydrocarbon tail that is 20 carbons long undergo? What are the products?
Each round of beta oxidation yields one molecule of acetyl-CoA (along with one molecule of FADH2 and one molecule of NADH). Both electron carriers feed into the electron transport chain, ultimately yielding ATP via chemiosmosis. Since the organic product of beta oxidation (acetyl-CoA) contains two carbons, nine rounds of beta oxidation are required to fully oxidize a fatty acid with a 20-carbon hydrocarbon tail. Recognize that it is NOT 10 rounds because the last round (9th) will cut the now 4-carbon hydrocarbon tail, yielding two acetyl-CoA molecules. As a rule, a fatty acid with a hydrocarbon tail of 
of carbons undergoes 
rounds of beta oxidation to be full oxidized.
Overall, for a fatty acid with 20 carbons in its hydrocarbon chain, 9 rounds of beta oxidation yielding 10 molecules of acetyl-CoA constitutes complete oxidation.
Each round of beta oxidation yields one molecule of acetyl-CoA (along with one molecule of FADH2 and one molecule of NADH). Both electron carriers feed into the electron transport chain, ultimately yielding ATP via chemiosmosis. Since the organic product of beta oxidation (acetyl-CoA) contains two carbons, nine rounds of beta oxidation are required to fully oxidize a fatty acid with a 20-carbon hydrocarbon tail. Recognize that it is NOT 10 rounds because the last round (9th) will cut the now 4-carbon hydrocarbon tail, yielding two acetyl-CoA molecules. As a rule, a fatty acid with a hydrocarbon tail of
Overall, for a fatty acid with 20 carbons in its hydrocarbon chain, 9 rounds of beta oxidation yielding 10 molecules of acetyl-CoA constitutes complete oxidation.
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Which of the following is not a product of beta oxidation of fatty acids?
Which of the following is not a product of beta oxidation of fatty acids?
One round of beta oxidation of fatty acids removes 2 carbons off the fatty acid chain at a time, yielding acetyl-CoA as well as 
and 
(from the 2 oxidation steps). ATP is not a direct product of beta oxidation, however the acetyl-CoA and reduced coenzymes will provide ATP via Krebs cycle and electron transport.
One round of beta oxidation of fatty acids removes 2 carbons off the fatty acid chain at a time, yielding acetyl-CoA as well as
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In plants, a cycle known as the glyoxylate cycle exists, which allows plants to synthesize carbohydrates from fats. This is how fat-rich seeds are anabolized to produce carbohydrates in plants.
Even though the glyoxylate cycle does not exist in humans, there is one molecule that is used in gluconeogenesis that comes from 
-oxidation of fatty acids. Which molecule is this?
In plants, a cycle known as the glyoxylate cycle exists, which allows plants to synthesize carbohydrates from fats. This is how fat-rich seeds are anabolized to produce carbohydrates in plants.
Even though the glyoxylate cycle does not exist in humans, there is one molecule that is used in gluconeogenesis that comes from
-oxidation of fatty acids yields large quantities of acetyl-CoA, all of which enters the citric acid cycle. The only intermediate in the citric acid cycle that can form back into glucose is oxaloacetate. It can be turned into phosphoenolpyruvate via phosphoenolpyruvate carboxykinase.
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What is the first step of the beta oxidation of fatty acids?
What is the first step of the beta oxidation of fatty acids?
In the first step of beta oxidation the enzyme acyl-CoA dehydrogenase forms a trans-double bond between the two carbons at the site that will eventually be cleaved.
In the first step of beta oxidation the enzyme acyl-CoA dehydrogenase forms a trans-double bond between the two carbons at the site that will eventually be cleaved.
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On average, how many ATP and GTP molecules can be generated from an eighteen-carbon fatty acid?
On average, how many ATP and GTP molecules can be generated from an eighteen-carbon fatty acid?
First, one must know what the products of one cycle of the beta oxidation pathway are. Each cycle yields 
, 
, 1 acetyl-CoA, and a fatty acyl-CoA molecule 2 carbons shorter than the original.
Therefore, an eighteen-carbon fatty acyl-CoA input can go through the beta oxidation cycle 8 times (the last round only a 2 carbon acetyl CoA remains, which cannot enter the beta oxidation pathway again). That means there are 
molecules, 9 acetyl-CoA molecules, and 
molecules that can be generated from an eighteen-carbon fatty acyl-CoA.
It may be confusing to understand why there are only 
and 
molecules and 9 acetyl-CoA, but if one is solving a problem such as this for the first time, go through and draw out the products following each round of the beta oxidation cycle.
2.5 ATP on average can be formed from each 
molecule, and 1.5 ATP from each 
molecule through the electron transport chain. 10 ATP can be formed in total from one acetyl-CoA entering into the Krebs cycle (by the products of 
and 
), along with one GTP molecule.
Therefore:
If taken into consideration, 2 ATP are needed to activate a fatty acid and allow it to enter into the mitochondria via the enzyme acyl-CoA synthetase.
Therefore, the toTal net yield is 
For a quick reference, the following equations can be used:
Where 
is number of carbons of aneven numbered fatty acid chain.
First, one must know what the products of one cycle of the beta oxidation pathway are. Each cycle yields
Therefore, an eighteen-carbon fatty acyl-CoA input can go through the beta oxidation cycle 8 times (the last round only a 2 carbon acetyl CoA remains, which cannot enter the beta oxidation pathway again). That means there are
It may be confusing to understand why there are only
2.5 ATP on average can be formed from each
Therefore:
If taken into consideration, 2 ATP are needed to activate a fatty acid and allow it to enter into the mitochondria via the enzyme acyl-CoA synthetase.
Therefore, the toTal net yield is
For a quick reference, the following equations can be used:
Where
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How many molecules of acetyl-CoA can be expected to be produced from the beta-oxidation of palmitic acid?
Note: Palmitic acid is a saturated fatty acid containing sixteen carbon atoms.
How many molecules of acetyl-CoA can be expected to be produced from the beta-oxidation of palmitic acid?
Note: Palmitic acid is a saturated fatty acid containing sixteen carbon atoms.
For each round of beta-oxidation, two carbon atoms are removed from the fatty acid chain. These two carbon atoms come off of the chain in the form of acetyl-CoA. Additionally, high energy electron carriers in the form of NADH and 
are also produced, thus making beta-oxidation a process that liberates a great deal of energy.
Since the fatty acid that we're starting with has a total of 
carbon atoms, we can expect there to be a total of 
acetyl-CoA molecules produced, since each of these contains two carbons from the fatty acid.
For each round of beta-oxidation, two carbon atoms are removed from the fatty acid chain. These two carbon atoms come off of the chain in the form of acetyl-CoA. Additionally, high energy electron carriers in the form of NADH and
Since the fatty acid that we're starting with has a total of
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Which of the following molecules is/are the product(s) at the end of normal beta oxidation of a fatty acid?
Which of the following molecules is/are the product(s) at the end of normal beta oxidation of a fatty acid?
During beta oxidation of fatty acids, carbons are removed from the fatty acid chain two at a time. So when a fatty acid is composed of an even number of carbons (as most are) 4 carbons will be left at the end. This will be cleaved into two separate 2 carbon molecules - two acetyl-CoA molecules.
During beta oxidation of fatty acids, carbons are removed from the fatty acid chain two at a time. So when a fatty acid is composed of an even number of carbons (as most are) 4 carbons will be left at the end. This will be cleaved into two separate 2 carbon molecules - two acetyl-CoA molecules.
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Which of the following molecules is/are produced at the end of beta oxidation of a fatty acid with an odd number of carbons in its carbon chain?
Which of the following molecules is/are produced at the end of beta oxidation of a fatty acid with an odd number of carbons in its carbon chain?
During beta-oxidation of fatty acids, carbons are removed from the fatty acid chain two at a time. So when a fatty acid is composed of an odd number of carbons, 5 carbons will be left at the end. This will be cleaved into two separate molecules - one with 3 carbons and one with 2 carbons. This is one acetyl-CoA molecule (2 carbons) and one propionyl-CoA molecule (3 carbons).
During beta-oxidation of fatty acids, carbons are removed from the fatty acid chain two at a time. So when a fatty acid is composed of an odd number of carbons, 5 carbons will be left at the end. This will be cleaved into two separate molecules - one with 3 carbons and one with 2 carbons. This is one acetyl-CoA molecule (2 carbons) and one propionyl-CoA molecule (3 carbons).
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During beta oxidation, what is the end product of a fatty acid with an odd number of carbons?
During beta oxidation, what is the end product of a fatty acid with an odd number of carbons?
Fatty acids with an odd number of carbons are more common in plants and marine organisms than they are in mammals. When humans consume these organisms in their diets, they must metabolize them through beta oxidation. The end product of this reaction is propionyl-CoA rather than acetyl-CoA, which is formed during cleavage of two-carbon segments (fatty acids with an even number of carbons). Before entering the Krebs cycle, the propionyl-CoA must be transformed into succinyl-CoA.
Fatty acids with an odd number of carbons are more common in plants and marine organisms than they are in mammals. When humans consume these organisms in their diets, they must metabolize them through beta oxidation. The end product of this reaction is propionyl-CoA rather than acetyl-CoA, which is formed during cleavage of two-carbon segments (fatty acids with an even number of carbons). Before entering the Krebs cycle, the propionyl-CoA must be transformed into succinyl-CoA.
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