diabetestalk.net

Which Compound Cannot Be Converted To Glucose?

Share on facebook

ilmkidunya.com has brought to you Lecture of Usama Qamar on "9th Class Biology Chapter 1 Introduction to Biology. Topic 1 Introduction Chapter 1". In this video following sub topics have been taught: - Division of Biology - Main Branches of Biology For more videos of Usama Qamar visit https://www.ilmkidunya.com/study This lecture is specially recorded for students of 9th class, 9th class from all Punjab Boards and is based on the current curriculum of study for Biology book. All these lectures are conducted in Urdu/English medium to facilitate Pakistani students.

Chapter Outline

Coenzymes are organic enzyme "assistants." Some vitamins act as coenzymes. Cofactors are compounds (organic or inorganic) that facilitate enzyme action. Minerals are inorganic cofactors. ATP is generated via 3 metabolic pathways: The TCA (Krebs) cycle, which occurs in the MITOCHONDRIA. The electron transport chain, which occurs in the MITOCHONDRIA. The breakdown of glucose for energy starts with the process of glycolysis, which ultimately yields pyruvate. Pyruvate subsequently may be converted to lactic acid (via anaerobic means) or acetyl CoA (via aerobic means). Eventually, fragments of all energy-yielding nutrients enter the TCA cycle (Kreb's cycle) and the electron transport chain (ETC). Important compounds in energy metabolism: If you are one of those individuals, as I am, who likes to see the complete chemical structures when talking about the various reactions, etc., those structures can be found in Appendix C in your textbook. excreted through the kidneys (in the urine) (Figure 7-17) A high blood urea nitrogen (BUN) level is an indicator of impaired kidney function. A high level ammonia in the blood indicates impaired liver function (inability to convert ammonia to urea). Continue reading >>

Share on facebook

Popular Questions

  1. manohman

    Why can't fat be converted into Glucose?

    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?

  2. Czarcasm

    manohman said: ↑
    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?
    Click to expand... Both glucose and fatty acids can be stored in the body as either glycogen for glucose (stored mainly in the liver or skeletal cells) or for FA's, as triacylglycerides (stored in adipose cells). We cannot store excess protein. It's either used to make other proteins, or flushed out of the body if in excess; that's generally the case but we try to make use of some of that energy instead of throwing it all away.
    When a person is deprived of nutrition for a period of time and glycogen stores are depleted, the body will immediately seek out alternative energy sources. Fats (stored for use) are the first priority over protein (which requires the breakdown of tissues such as muscle). We can mobilize these FA's to the liver and convert them to Acetyl-CoA to be used in the TCA cycle and generate much needed energy. On the contrary, when a person eats in excess (a fatty meal high in protein), it's more efficient to store fatty acids as TAG's over glycogen simply because glycogen is extremely hydrophilic and attracts excess water weight; fatty acids are largely stored anhydrously and so you essentially get more bang for your buck. This is evolutionary significant and why birds are able to stay light weight but fly for periods at a time, or why bears are able to hibernate for months at a time. Proteins on the other hand may be used anabolically to build up active tissues (such as when your working out those muscles), unless you live a sedentary lifestyle (less anabolism and therefore, less use of the proteins). As part of the excretion process, protein must be broken down to urea to avoid toxic ammonia and in doing so, the Liver can extract some of that usable energy for storage as glycogen.
    Also, it is worth noting that it is indeed possible to convert FA's to glucose but the pathway can be a little complex and so in terms of energy storage, is not very efficient. The process involves converting Acetyl-CoA to Acetone (transported out of mitochondria to cytosol) where it's converted to Pyruvate which can then be used in the Gluconeogenesis pathway to make Glucose and eventually stored as Glycogen. Have a look for yourself if your interested: http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002116.g003/originalimage (and this excludes the whole glycogenesis pathway, which hasn't even begun yet).
    TLDR: it's because proteins have no ability to be stored in the body, but we can convert them to glycogen for storage during the breakdown process for excretion. Also, in terms of energy, it's a more efficient process than converting FA's to glycogen for storage.

  3. soccerman93

    This is where biochem comes in handy. Czarcasm gives a really good in depth answer, but a simpler approach is to count carbons. The first step of gluconeogenesis(formation of glucose) requires pyruvate, a 3 carbon molecule. Acetyl Co-A is a 2 carbon molecule, and most animals lack the enzymes (malate synthase and isocitrate lyase) required to convert acetyl co-A into a 3 carbon molecule suitable for the gluconeogenesis pathway. The ketogenic pathway is not efficient, as czarcasm pointed out. While acetyl co-A can indeed be used to form citric acid intermediates, these intermediates will be used in forming ATP, not glucose. Fatty acid oxidation does not yield suitable amounts of pyruvate, which is required for gluconeogenesis. This is part of why losing weight is fairly difficult for those that are overweight, we can't efficiently directly convert fat to glucose, which we need a fairly constant supply of. Sorry, that got a little long-winded

  4. -> Continue reading
read more
Share on facebook

In this video I discuss what is fructose, fructose metabolism, and fructose in sugar. Transcript (partial) Fructose is a monosaccharide, which are the most basic units of carbs. Pure, dry fructose is very sweet, white, and odorless. It is found in honey, fruits, vegetables, sugar cane, and sugar beets. Usually fructose is separated from glucose in a sucrose molecule. It can then be added as a stand alone ingredient. Because pure fructose is sweeter than sugar, less of it can be used to achieve the same level of sweetness, which translates to lower calorie foods. 1 teaspoon of Pure dry fructose has 15 calories, which equates to 4.2g of carbs. How does the body use fructose? Most of the cells in our body cant process fructose, so,it is almost completely metabolized in the liver through a process called fructolysis. Essentially the liver converts fructose to energy, but, this energy cant leave because of its molecular makeup. The liver does burn off some of this energy . If there is any excess fructose after the energy conversion, the liver stores it as glycogen, which can be broken down into glucose and sent to other cells for use. But the liver can only store so much glycogen, once it is fully stocked in glycogen, the extra fructose is used to create triglycerides, which can be moved outside the liver for long term storage as fat. So, based on this, fruits must be bad? Actually, No, not at all. Fruits are loaded with water, fiber, and other nutrients, so, they take a while to eat and digest so, their fructose hits the liver slowly. The amount of fructose contained in fruit is much smaller than the added sugar in a soft drink for instance. Bottom linefructose is not unhealthy, depending on the source it came from. When that source is a natural food, like fruits and vegetables great, when that source is in the form of added sugar, not so great.

Metabolism - Reason For Conversion Of Glucose To Fructose In Glycolysis - Biology Stack Exchange

Reason for conversion of glucose to fructose in glycolysis In glycolysis, glucose is converted to glucose 6-phosphate so it can not diffuse out of the membrane. Then it is converted to fructose 6-phosphate. Why is this? Perhaps it makes it less stable so it is easier to break down into pyruvate? That is just a guess, is anyone able to provide more information about this? Don't guess. Please do some research before posting basic questions that can be answered by reading a text book of biochemistry. For example Chapter 16 of Berg et al. online. David Aug 30 '17 at 21:20 However as I do not think either of the answers (including the one you accepted) are adequate, the point is less obvious than I imagined. I have therefore provided my own answer. David Sep 6 '17 at 13:45 In glycolysis, free energy (sequestered in the form of ATP) is derived from the splitting of glucose. One mechanistic explanation for the conversion of glucose to fructose is that it facilitates splitting of glucose via (reverse) aldol condensation (in the aldolase reaction) as aldol condensations are are 'facilitated' by having a carbonyl group next to the site of cleavage.. See this great article for a much better Continue reading >>

Share on facebook

Popular Questions

  1. manohman

    Why can't fat be converted into Glucose?

    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?

  2. Czarcasm

    manohman said: ↑
    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?
    Click to expand... Both glucose and fatty acids can be stored in the body as either glycogen for glucose (stored mainly in the liver or skeletal cells) or for FA's, as triacylglycerides (stored in adipose cells). We cannot store excess protein. It's either used to make other proteins, or flushed out of the body if in excess; that's generally the case but we try to make use of some of that energy instead of throwing it all away.
    When a person is deprived of nutrition for a period of time and glycogen stores are depleted, the body will immediately seek out alternative energy sources. Fats (stored for use) are the first priority over protein (which requires the breakdown of tissues such as muscle). We can mobilize these FA's to the liver and convert them to Acetyl-CoA to be used in the TCA cycle and generate much needed energy. On the contrary, when a person eats in excess (a fatty meal high in protein), it's more efficient to store fatty acids as TAG's over glycogen simply because glycogen is extremely hydrophilic and attracts excess water weight; fatty acids are largely stored anhydrously and so you essentially get more bang for your buck. This is evolutionary significant and why birds are able to stay light weight but fly for periods at a time, or why bears are able to hibernate for months at a time. Proteins on the other hand may be used anabolically to build up active tissues (such as when your working out those muscles), unless you live a sedentary lifestyle (less anabolism and therefore, less use of the proteins). As part of the excretion process, protein must be broken down to urea to avoid toxic ammonia and in doing so, the Liver can extract some of that usable energy for storage as glycogen.
    Also, it is worth noting that it is indeed possible to convert FA's to glucose but the pathway can be a little complex and so in terms of energy storage, is not very efficient. The process involves converting Acetyl-CoA to Acetone (transported out of mitochondria to cytosol) where it's converted to Pyruvate which can then be used in the Gluconeogenesis pathway to make Glucose and eventually stored as Glycogen. Have a look for yourself if your interested: http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002116.g003/originalimage (and this excludes the whole glycogenesis pathway, which hasn't even begun yet).
    TLDR: it's because proteins have no ability to be stored in the body, but we can convert them to glycogen for storage during the breakdown process for excretion. Also, in terms of energy, it's a more efficient process than converting FA's to glycogen for storage.

  3. soccerman93

    This is where biochem comes in handy. Czarcasm gives a really good in depth answer, but a simpler approach is to count carbons. The first step of gluconeogenesis(formation of glucose) requires pyruvate, a 3 carbon molecule. Acetyl Co-A is a 2 carbon molecule, and most animals lack the enzymes (malate synthase and isocitrate lyase) required to convert acetyl co-A into a 3 carbon molecule suitable for the gluconeogenesis pathway. The ketogenic pathway is not efficient, as czarcasm pointed out. While acetyl co-A can indeed be used to form citric acid intermediates, these intermediates will be used in forming ATP, not glucose. Fatty acid oxidation does not yield suitable amounts of pyruvate, which is required for gluconeogenesis. This is part of why losing weight is fairly difficult for those that are overweight, we can't efficiently directly convert fat to glucose, which we need a fairly constant supply of. Sorry, that got a little long-winded

  4. -> Continue reading
read more
Share on facebook

Moof's Medical Biochemistry Video Course: http://moof-university.thinkific.com/... In this video, I define and describe glucogenic and ketogenic amino acids, as well as list and depict which amino acids are exclusively glucogenic, which amino acids are exclusively ketogenic, and which amino acids are both glucogenic and ketogenic. I also show how the amino acids feed into the different key products of the TCA Cycle. For a suggested viewing order of the videos, information on tutoring, personalized video solutions, and an opportunity to support Moof University financially, visit MoofUniversity.com, and follow Moof University on the different social media platforms. Don't forget to LIKE, COMMENT, and SUBSCRIBE: http://www.youtube.com/subscription_c...

Ketogenic Amino Acid

All mammals synthesize saturated fatty and monounsaturated fatty acids de novo from simple precursors such as glucose or ketogenic amino acids. However, mammals cannot insert double bonds more proximal to the methyl end than the ninth carbon atom. Thus, two fatty acids having their first double bonds at the 6th and 3rd carbon atoms, namely, linoleic (18:2 n-6) and alpha-linolenic acid (18:3 n-3), respectively, cannot be synthesized de novo. Therefore, these fatty acids have to be supplied through the diet and are called essential fatty acids. Denoting the position of the first double bond proximal to the methyl end of the fatty acid chain, essential fatty acids are also classified as omega-6 (n-6) and omega-3 (n-3) fatty acids. A list of the most common n-3 and n-6 fatty acids and their systemic, common name, and shorthand notation is shown in Table 28.1. As early as the1930s, the essentiality of linoleic acid (18:2 n-6) and alpha-linolenic acid (18:3 n-3) in rat diets was identified (Burr and Burr, 1930). However, the essentiality of n-3 fatty acids in humans was first demonstrated only in the early 1980s (Holman et al., 1982). M. Saleet Jafri*, Rashmi Kumar, in Progress in Molec Continue reading >>

Share on facebook

Popular Questions

  1. manohman

    Why can't fat be converted into Glucose?

    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?

  2. Czarcasm

    manohman said: ↑
    So the reason cited is that beta oxidation/metabolism of fats leads to formation of acetyl coa, a 2 carbon molecule, and that because of that it cannot be converted back into glucose.
    Why exactly is that the case?
    If Glucogenic amino acids can be converted into citric acid cycle intermediates and then turn back into glucose via gluconeogensis, then why cant Fatty Acids which yield Acetyl Coa. Can't you just have Acetyl Coa enter the citric acid cycle and produce the same intermediates that the glucogenic amino acids creat?
    Click to expand... Both glucose and fatty acids can be stored in the body as either glycogen for glucose (stored mainly in the liver or skeletal cells) or for FA's, as triacylglycerides (stored in adipose cells). We cannot store excess protein. It's either used to make other proteins, or flushed out of the body if in excess; that's generally the case but we try to make use of some of that energy instead of throwing it all away.
    When a person is deprived of nutrition for a period of time and glycogen stores are depleted, the body will immediately seek out alternative energy sources. Fats (stored for use) are the first priority over protein (which requires the breakdown of tissues such as muscle). We can mobilize these FA's to the liver and convert them to Acetyl-CoA to be used in the TCA cycle and generate much needed energy. On the contrary, when a person eats in excess (a fatty meal high in protein), it's more efficient to store fatty acids as TAG's over glycogen simply because glycogen is extremely hydrophilic and attracts excess water weight; fatty acids are largely stored anhydrously and so you essentially get more bang for your buck. This is evolutionary significant and why birds are able to stay light weight but fly for periods at a time, or why bears are able to hibernate for months at a time. Proteins on the other hand may be used anabolically to build up active tissues (such as when your working out those muscles), unless you live a sedentary lifestyle (less anabolism and therefore, less use of the proteins). As part of the excretion process, protein must be broken down to urea to avoid toxic ammonia and in doing so, the Liver can extract some of that usable energy for storage as glycogen.
    Also, it is worth noting that it is indeed possible to convert FA's to glucose but the pathway can be a little complex and so in terms of energy storage, is not very efficient. The process involves converting Acetyl-CoA to Acetone (transported out of mitochondria to cytosol) where it's converted to Pyruvate which can then be used in the Gluconeogenesis pathway to make Glucose and eventually stored as Glycogen. Have a look for yourself if your interested: http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002116.g003/originalimage (and this excludes the whole glycogenesis pathway, which hasn't even begun yet).
    TLDR: it's because proteins have no ability to be stored in the body, but we can convert them to glycogen for storage during the breakdown process for excretion. Also, in terms of energy, it's a more efficient process than converting FA's to glycogen for storage.

  3. soccerman93

    This is where biochem comes in handy. Czarcasm gives a really good in depth answer, but a simpler approach is to count carbons. The first step of gluconeogenesis(formation of glucose) requires pyruvate, a 3 carbon molecule. Acetyl Co-A is a 2 carbon molecule, and most animals lack the enzymes (malate synthase and isocitrate lyase) required to convert acetyl co-A into a 3 carbon molecule suitable for the gluconeogenesis pathway. The ketogenic pathway is not efficient, as czarcasm pointed out. While acetyl co-A can indeed be used to form citric acid intermediates, these intermediates will be used in forming ATP, not glucose. Fatty acid oxidation does not yield suitable amounts of pyruvate, which is required for gluconeogenesis. This is part of why losing weight is fairly difficult for those that are overweight, we can't efficiently directly convert fat to glucose, which we need a fairly constant supply of. Sorry, that got a little long-winded

  4. -> Continue reading
read more

No more pages to load

Related Articles

  • Which Insulin Cannot Be Mixed With Any Other Insulin?

    Insulin is necessary for normal carbohydrate, protein, and fat metabolism. People with type 1 diabetes mellitus do not produce enough of this hormone to sustain life and therefore depend on exogenous insulin for survival. In contrast, individuals with type 2 diabetes are not dependent on exogenous insulin for survival. However, over time, many of these individuals will show decreased insulin production, therefore requiring supplemental insulin fo ...

    insulin Apr 11, 2018
  • Which Insulins Cannot Be Mixed

    Not so long ago, if you used insulin, you didn't have a whole lot of choices. There was "normal" speed R insulin, slower NPH or Lente, and perhaps you considered using Ultralente. You used Lilly insulins, or those from Novo Nordisk. It was that way for decades. No longer. Insulin innovations have come thick and fast. It is tough for us, and our doctors, to keep up. It seems every time we turn around there's not only a new oral diabetes medication ...

    insulin Apr 6, 2018
  • Which Compound Cannot Be Converted To Glucose?

    Gluconeogenesis (abbreviated GNG) is a metabolic pathway that results in the generation of glucose from non-carbohydrate carbon substrates such as lactate, glycerol, and glucogenic amino acids. It is one of the two main mechanisms humans and many other animals use to keep blood glucose levels from dropping too low (hypoglycemia). The other means of maintaining blood glucose levels is through the degradation of glycogen (glycogenolysis). Gluconeog ...

    ketosis Apr 27, 2018
  • Typical Fatty Acids Cannot Be Converted To Glucose Because

    Biochemistry textbooks generally tell us that we can’t turn fatty acids into glucose. For example, on page 634 of the 2006 and 2008 editions of Biochemistry by Berg, Tymoczko, and Stryer, we find the following: Animals Cannot Convert Fatty Acids to Glucose It is important to note that animals are unable to effect the net synthesis of glucose from fatty acids. Specficially, acetyl CoA cannot be converted into pyruvate or oxaloacetate in animals. ...

    ketosis Apr 1, 2018
  • Is Glucose A Compound Or A Molecule?

    This article is about the naturally occurring D-form of glucose. For the L-form, see L-Glucose. Glucose is a simple sugar with the molecular formula C6H12O6, which means that it is a molecule that is made of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. Glucose circulates in the blood of animals as blood sugar. It is made during photosynthesis from water and carbon dioxide, using energy from sunlight. It is the most important sou ...

    blood sugar Apr 27, 2018
  • What Percentage Of A Triglyceride Molecule Cannot Be Converted To Glucose At All?

    Despite the fact that eating a jelly doughnut seems to deposit fat directly on your hips, converting sugar to fat is actually a relatively complex chemical process. Sugar conversion to fat storage depends not only upon the type of foods you eat, but how much energy your body needs at the time you eat it. Video of the Day Your body converts excess dietary glucose into fat through the process of fatty acid synthesis. Fatty acids are required in ord ...

    ketosis Jan 16, 2018

Popular Articles

More in ketosis