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How Do You Produce Glucose?

The Liver & Blood Sugar

The Liver & Blood Sugar

During a meal, your liver stores sugar for later. When you’re not eating, the liver supplies sugar by turning glycogen into glucose in a process called glycogenolysis. The liver both stores and produces sugar… The liver acts as the body’s glucose (or fuel) reservoir, and helps to keep your circulating blood sugar levels and other body fuels steady and constant. The liver both stores and manufactures glucose depending upon the body’s need. The need to store or release glucose is primarily signaled by the hormones insulin and glucagon. During a meal, your liver will store sugar, or glucose, as glycogen for a later time when your body needs it. The high levels of insulin and suppressed levels of glucagon during a meal promote the storage of glucose as glycogen. The liver makes sugar when you need it…. When you’re not eating – especially overnight or between meals, the body has to make its own sugar. The liver supplies sugar or glucose by turning glycogen into glucose in a process called glycogenolysis. The liver also can manufacture necessary sugar or glucose by harvesting amino acids, waste products and fat byproducts. This process is called gluconeogenesis. When your body’s glycogen storage is running low, the body starts to conserve the sugar supplies for the organs that always require sugar. These include: the brain, red blood cells and parts of the kidney. To supplement the limited sugar supply, the liver makes alternative fuels called ketones from fats. This process is called ketogenesis. The hormone signal for ketogenesis to begin is a low level of insulin. Ketones are burned as fuel by muscle and other body organs. And the sugar is saved for the organs that need it. The terms “gluconeogenesis, glycogenolysis and ketogenesis” may seem like compli Continue reading >>

Glucose

Glucose

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 source of energy for cellular respiration. Glucose is stored as a polymer, in plants as starch and in animals as glycogen. With six carbon atoms, it is classed as a hexose, a subcategory of the monosaccharides. D-Glucose is one of the sixteen aldohexose stereoisomers. The D-isomer, D-glucose, also known as dextrose, occurs widely in nature, but the L-isomer, L-glucose, does not. Glucose can be obtained by hydrolysis of carbohydrates such as milk sugar (lactose), cane sugar (sucrose), maltose, cellulose, glycogen, etc. It is commonly commercially manufactured from cornstarch by hydrolysis via pressurized steaming at controlled pH in a jet followed by further enzymatic depolymerization.[3] In 1747, Andreas Marggraf was the first to isolate glucose.[4] Glucose is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system.[5] The name glucose derives through the French from the Greek γλυκός, which means "sweet," in reference to must, the sweet, first press of grapes in the making of wine.[6][7] The suffix "-ose" is a chemical classifier, denoting a carbohydrate. Function in biology[edit] Glucose is the most widely used aldohexose in living organisms. One possible explanation for this is that glucose has a lower tendency than other aldohexoses to react nonspecific Continue reading >>

Renal Glucose Production And Utilization: New Aspects In Humans.

Renal Glucose Production And Utilization: New Aspects In Humans.

Renal glucose production and utilization: new aspects in humans. Medizinische Universittsklinik, Tubingen, Germany. According to current textbook wisdom the liver is the exclusive site of glucose production in humans in the postabsorptive state. Although many animal and in vitro data have documented that the kidney is capable of gluconeogenesis, production of glucose by the human kidney in the postabsorptive state has generally been regarded as negligible. This traditional view is based on net balance measurements which, other than after a prolonged fast or during metabolic acidosis, showed no significant net renal glucose release. However, recent studies have refuted this view by combining isotopic and balance techniques, which have demonstrated that renal glucose production accounts for 25% of systemic glucose production. Moreover, these studies indicate that glucose production by the human kidney is stimulated by epinephrine, inhibited by insulin and is excessive in diabetes mellitus. Since renal glucose release is largely, if not exclusively, due to gluconeogenesis, it is likely that the kidney is as important a gluconeogenic organ as the liver. The most important renal gluconeogenic precursors appear to be lactate, glutamine and glycerol. The implications of these recent findings on the understanding of the physiology and pathophysiology of human glucose metabolism are discussed. Continue reading >>

How The Body Produces Glucose When We Are Fasting

How The Body Produces Glucose When We Are Fasting

Glucose is our main source of energy and it is therefore important that there are physiological pathways in place to prevent blood glucose from dropping dangerously low when we are fasting, for example when sleeping at night. Gluconeogenesis: producing glucose from non-carbohydrate sources The gluconeogenesis pathway (see metabolism figure below) synthesises new glucose using non-carbohydrate precursors (glycerol from the breakdown of triglycerides, lactate during anaerobic glycolysis and amino acids from muscle protein degradation). 90% of gluconeogenesis occurs in the liver but some occurs in the kidney too. Insulin regulates gluconeogenesis. The newly made glucose is released back into the blood stream to raise blood glucose levels. Glycogenolysis: release of glucose from stored glycogen In the glycogenolysis pathway (see metabolism figure above), liver glycogen can be broken down to produce glucose which is released back into the blood stream to increase blood glucose concentrations. The combination of these processes enables us to maintain a low but significant level of glucose, despite fasting or even starvation (see figure below). So you can see from the diagram above that the blood glucose (black line) is kept constant by a combination of processes: release of glucose from the diet (red line), gluconeogenesis (blue) and glycogenolysis (green). © University of Southampton 2017 Continue reading >>

Where Does Glucose Come From In Plants?

Where Does Glucose Come From In Plants?

2009-09-17Where Does Glucose Come From in Plants? In a typical ecosystem, plants are the producers. Plants take energy from the sun and through a process called photosynthesis, produce food. The food is sugar or glucose. In order to produce glucose, a plant needs the raw materials in order for photosynthesis to occur: light energy from the sun, water from the environment and carbon dioxide from the atmosphere. Sunlight is the catalyst for photosynthesis. The process occurs primarily in the leaves. The light energy bring about a chemical reaction between water and carbon dioxide that occurs in the chloroplasts within the leaves. Chloroplasts are mini-organs or organelles within the plant cells. The energy splits the water molecules into its two components, oxygen and hydrogen. Oxygen leaves the plant through respiration. This is the source of oxygen in our atmosphere. Photosynthesis consists of two processes, a light reaction and a dark reaction. As the names would imply, sunlight is required for the light reaction to happen. Without light, the plant is unable to produce energy in the form of adenosine triphosphate (ATP). This is the same energy chemical that we use to fuel any cell process in our bodies. The dark reaction also occurs within the chloroplasts. This is when sugar is produced. Light isn't necessary as it is for the light reaction, but the product of it is required. ATP, another chemical called NADPH (nicotinamide adenine dinucleotide phosphate-oxidase) and carbon dioxide through a chemical process called the Calvin cycle produce glucose. Chlorophyll is responsible for channeling the energy necessary for photosynthesis. It is also responsible for the green color of plants. The green color reflects the light waves from the sun which are not absorbed by the p Continue reading >>

Sources Of Glucose

Sources Of Glucose

Our bodies convert food into energy. Although we get energy and calories from carbohydrate, protein, and fat, our main source of energy is from carbohydrate. Our bodies convert carbohydrate into glucose, a type of sugar. See Illustration: How Food Affects Blood Sugar Many foods contain a combination of carbohydrate, protein, and fat. The amount of each in the food we eat affects how quickly our bodies change that food into glucose. This is how different foods affect how our blood sugar levels: Carbohydrate: Includes bread, rice, pasta, potatoes, vegetables, fruit, sugar, yogurt, and milk. Our bodies change 100 percent of the carbohydrate we eat into glucose. This affects our blood sugar levels quickly, within an hour or two after eating Protein: Includes fish, meat, cheese, and peanut butter. Although our bodies change some of the protein we eat into glucose, most of this glucose is stored in our liver and not released into our bloodstream. Eating protein usually has very little impact on blood sugar. Fat: Includes butter, salad dressing, avocado, olive oil. We turn less than 10 percent of the fat we eat into glucose. The glucose from fat is absorbed slowly and it won't cause an immediate rise in blood sugar. Even though we don't get much glucose from fat, a meal that's high in fat can affect how fast our bodies digest carbohydrate. Because fat slows down the digestion of carbohydrate, it also slows down the rise in blood sugar levels. This sometimes can cause a high blood sugar level several hours after eating. For some people, this delayed reaction can be quite a surprise. For example, after eating a meal high in fat, a person might have a blood sugar reading that's close to normal before going to bed. But the next morning, he or she might have a fasting blood sugar t Continue reading >>

How Do Plants Produce Glucose?

How Do Plants Produce Glucose?

Plants need light to produce glucose. (Image: ULTRA.F/Photodisc/Getty Images) Plants produce glucose through a process known as photosynthesis. Plants absorb the materials it needs and carry out chemical processes that transform these materials into glucose, which plants need for energy. To produce glucose, a plant needs water, which it absorbs using roots and transports to the leaves. The plant opens its stomata, which are tiny holes on leaves, to obtain carbon dioxide. The plant also uses specialized molecules known as chlorophyll to obtain energy from light. Using energy from light, the plant turns water and carbon dioxide into glucose and oxygen. The chemical reaction requires six molecules of water and six molecules of carbon dioxide to produce one molecule of sugar and six molecules of oxygen. Photosynthesis occurs in two stages. Light-dependent reactions turn light into energy-carrier molecules. Light-independent reactions use the energy carrier molecules to form the glucose molecules and can occur with or without light. Continue reading >>

Everything You Need To Know About Glucose

Everything You Need To Know About Glucose

You may know glucose by another name: blood sugar. Glucose is key to keeping the mechanisms of the body in top working order. When our glucose levels are optimal, it often goes unnoticed. But when they stray from recommended boundaries, you’ll notice the unhealthy effect it has on normal functioning. So what is glucose, exactly? It’s the simplest of the carbohydrates, making it a monosaccharide. This means it has one sugar. It’s not alone. Other monosaccharides include fructose, galactose, and ribose. Along with fat, glucose is one of the body’s preferred sources of fuel in the form of carbohydrates. People get glucose from bread, fruits, vegetables, and dairy products. You need food to create the energy that helps keep you alive. While glucose is important, like with so many things, it’s best in moderation. Glucose levels that are unhealthy or out of control can have permanent and serious effects. Our body processes glucose multiple times a day, ideally. When we eat, our body immediately starts working to process glucose. Enzymes start the breakdown process with help from the pancreas. The pancreas, which produces hormones including insulin, is an integral part of how our body deals with glucose. When we eat, our body tips the pancreas off that it needs to release insulin to deal with the rising blood sugar level. Some people, however, can’t rely on their pancreas to jump in and do the work it’s supposed to do. One way diabetes occurs is when the pancreas doesn’t produce insulin in the way it should. In this case, people need outside help (insulin injections) to process and regulate glucose in the body. Another cause of diabetes is insulin resistance, where the liver doesn’t recognize insulin that’s in the body and continues to make inappropriate am Continue reading >>

How Is Glucose Produced?

How Is Glucose Produced?

Your body thrives on glucose, which is the sugar it uses to synthesize energy. Carbohydrates supply glucose and other sugars that are converted into glucose. But it's such a vital source of energy that the body has a back-up system called gluconeogenesis. This metabolic pathway produces new glucose from noncarbohydrate sources. Video of the Day Carbohydrates are made from molecules of sugar connected together. Simple sugars consist of one to three sugar molecules, while starches contain hundreds to thousands of molecules, reports Colorado State University. The small intestine only absorbs single sugar molecules, which is why digestive enzymes break carbs down into the three monosaccharides: glucose, galactose and fructose. The monosaccharides travel to the liver, where glucose is generated when the liver turns galactose and fructose into glucose. The liver may send glucose into the bloodstream, where it’s transported to cells that need it for energy. If blood levels of glucose are high enough to meet your energy needs, the liver stores glucose by turning it into glycogen or fat. New Glucose Synthesis When the body produces glucose from something other than carbohydrates, the process is called gluconeogenesis. Most gluconeogenesis occurs in the liver, but a small amount also takes place in the kidneys and small intestine. Like carbs, fats and proteins are digested into smaller units. Glycerol from fats and amino acids from proteins may be used to make glucose. All amino acids except leucine and lysine can enter the gluconeogenesis pathway, but glutamine is the only one used in the kidneys and small intestine, according to Medical Biochemistry Page. Lactate is another substance used to synthesize new glucose. The boost in energy metabolism during intense exercise result Continue reading >>

The Liver And Blood Glucose Levels

The Liver And Blood Glucose Levels

Tweet Glucose is the key source of energy for the human body. Supply of this vital nutrient is carried through the bloodstream to many of the body’s cells. The liver produces, stores and releases glucose depending on the body’s need for glucose, a monosaccharide. This is primarily indicated by the hormones insulin - the main regulator of sugar in the blood - and glucagon. In fact, the liver acts as the body’s glucose reservoir and helps to keep your circulating blood sugar levels and other body fuels steady and constant. How the liver regulates blood glucose During absorption and digestion, the carbohydrates in the food you eat are reduced to their simplest form, glucose. Excess glucose is then removed from the blood, with the majority of it being converted into glycogen, the storage form of glucose, by the liver’s hepatic cells via a process called glycogenesis. Glycogenolysis When blood glucose concentration declines, the liver initiates glycogenolysis. The hepatic cells reconvert their glycogen stores into glucose, and continually release them into the blood until levels approach normal range. However, when blood glucose levels fall during a long fast, the body’s glycogen stores dwindle and additional sources of blood sugar are required. To help make up this shortfall, the liver, along with the kidneys, uses amino acids, lactic acid and glycerol to produce glucose. This process is known as gluconeogenesis. The liver may also convert other sugars such as sucrose, fructose, and galactose into glucose if your body’s glucose needs not being met by your diet. Ketones Ketones are alternative fuels that are produced by the liver from fats when sugar is in short supply. When your body’s glycogen storage runs low, the body starts conserving the sugar supplies fo Continue reading >>

Regulation Of Glucose Production By The Liver.

Regulation Of Glucose Production By The Liver.

Abstract Glucose is an essential nutrient for the human body. It is the major energy source for many cells, which depend on the bloodstream for a steady supply. Blood glucose levels, therefore, are carefully maintained. The liver plays a central role in this process by balancing the uptake and storage of glucose via glycogenesis and the release of glucose via glycogenolysis and gluconeogenesis. The several substrate cycles in the major metabolic pathways of the liver play key roles in the regulation of glucose production. In this review, we focus on the short- and long-term regulation glucose-6-phosphatase and its substrate cycle counter-part, glucokinase. The substrate cycle enzyme glucose-6-phosphatase catalyzes the terminal step in both the gluconeogenic and glycogenolytic pathways and is opposed by the glycolytic enzyme glucokinase. In addition, we include the regulation of GLUT 2, which facilitates the final step in the transport of glucose out of the liver and into the bloodstream. Continue reading >>

Bbc - Gcse Bitesize: Photosynthesis

Bbc - Gcse Bitesize: Photosynthesis

Photosynthesis captures energy for life on Earth. Many chemicals are made to allow life processes to occur in plants. These chemicals can move in and out of cells by the process of diffusion. Osmosis is a specific type of diffusion. Photosynthesis is a process used by plants in which energy from sunlight is used to convert carbon dioxide and water into molecules needed for growth. These molecules include sugars, enzymes and chlorophyll. Light energy is absorbed by the green chemical chlorophyll. This energy allows the production of glucose by the reaction between carbon dioxide and water. Oxygen is also produced as a waste product. This reaction can be summarised in the word equation: The chemical equation for photosynthesis is: Glucose is made up of carbon, hydrogen and oxygen atoms. Glucose made by the process of photosynthesis may be used in three ways: It can be converted into chemicals required for growth of plant cells such as cellulose It can be converted into starch, a storage molecule, that can be converted back to glucose when the plant requires it It can be broken down during the process of respiration, releasing energy stored in the glucose molecules Plants cells contain a number of structures that are involved in the process of photosynthesis: Diagram of a plant cell involved in production of glucose from photosynthesis Chloroplasts - containing chlorophyll and enzymes needed for reactions in photosynthesis. Nucleus - containing DNA carrying the genetic code for enzymes and other proteins used in photosynthesis Cell membrane - allowing gas and water to pass in and out of the cell while controlling the passage of other molecules Vacuole - containing cell sap to keep the cell turgid Cytoplasm - enzymes and other proteins used in photosynthesis made here Continue reading >>

Chemistry For Biologists: Photosynthesis

Chemistry For Biologists: Photosynthesis

Leaves and leaf structure | The structure of the chloroplast and photosynthetic membranes | Stages of photosynthesis | Non-cyclic phosphorylation (the Z scheme) | Chemiosmosis and ATP synthesis | Cyclic phosphorylation | The light-independent reactions | Summary of stages of photosynthesis | Factors affecting the rate of photosynthesis | Test your knowledge Photosynthesis is the process by which plants, some bacteria and some protistans use the energy from sunlight to produce glucose from carbon dioxide and water. This glucose can be converted into pyruvate which releases adenosine triphosphate (ATP) by cellular respiration. Oxygen is also formed. Photosynthesis may be summarised by the word equation: The conversion of usable sunlight energy into chemical energy is associated with the action of the green pigment chlorophyll. Chlorophyll is a complex molecule. Several modifications of chlorophyll occur among plants and other photosynthetic organisms. All photosynthetic organisms have chlorophyll a. Accessory pigments absorb energy that chlorophyll a does not absorb. Accessory pigments include chlorophyll b (also c, d, and e in algae and protistans), xanthophylls, and carotenoids (such as beta-carotene). Chlorophyll a absorbs its energy from the violet-blue and reddish orange-red wavelengths, and little from the intermediate (green-yellow-orange) wavelengths. a lipid-soluble hydrocarbon tail (C20H39 -) a flat hydrophilic head with a magnesium ion at its centre; different chlorophylls have different side-groups on the head The tail and head are linked by an ester bond. Plants are the only photosynthetic organisms to have leaves (and not all plants have leaves). A leaf may be viewed as a solar collector crammed full of photosynthetic cells. The raw materials of photosynthe Continue reading >>

What Is Glucose?

What Is Glucose?

Glucose comes from the Greek word for "sweet." It's a type of sugar you get from foods you eat, and your body uses it for energy. As it travels through your bloodstream to your cells, it's called blood glucose or blood sugar. Insulin is a hormone that moves glucose from your blood into the cells for energy and storage. People with diabetes have higher-than-normal levels in their blood. Either they don't have enough insulin to move it through or their cells don't respond to insulin as well as they should. High blood glucose for a long period of time can damage your kidneys, eyes, and other organs. How Your Body Makes Glucose It mainly comes from foods rich in carbohydrates, like bread, potatoes, and fruit. As you eat, food travels down your esophagus to your stomach. There, acids and enzymes break it down into tiny pieces. During that process, glucose is released. It goes into your intestines where it's absorbed. From there, it passes into your bloodstream. Once in the blood, insulin helps glucose get to your cells. Energy and Storage Your body is designed to keep the level of glucose in your blood constant. Beta cells in your pancreas monitor your blood sugar level every few seconds. When your blood glucose rises after you eat, the beta cells release insulin into your bloodstream. Insulin acts like a key, unlocking muscle, fat, and liver cells so glucose can get inside them. Most of the cells in your body use glucose along with amino acids (the building blocks of protein) and fats for energy. But it's the main source of fuel for your brain. Nerve cells and chemical messengers there need it to help them process information. Without it, your brain wouldn't be able to work well. After your body has used the energy it needs, the leftover glucose is stored in little bundles Continue reading >>

Facts About Diabetes And Insulin

Facts About Diabetes And Insulin

Diabetes is a very common disease, which, if not treated, can be very dangerous. There are two types of diabetes. They were once called juvenile-onset diabetes and adult diabetes. However, today we know that all ages can get both types so they are simply called type 1 and type 2 diabetes. Type 1, which occurs in approximately 10 percent of all cases, is an autoimmune disease in which the immune system, by mistake, attacks its own insulin-producing cells so that insufficient amounts of insulin are produced - or no insulin at all. Type 1 affects predominantly young people and usually makes its debut before the age of 30, and most frequently between the ages of 10 and 14. Type 2, which makes up the remaining 90 percent of diabetes cases, commonly affects patients during the second half of their lives. The cells of the body no longer react to insulin as they should. This is called insulin resistance. In the early 1920s, Frederick Banting, John Macleod, George Best and Bertram Collip isolated the hormone insulin and purified it so that it could be administered to humans. This was a major breakthrough in the treatment of diabetes type 1. Insulin Insulin is a hormone. Hormones are chemical substances that regulate the cells of the body and are produced by special glands. The hormone insulin is a main regulator of the glucose (sugar) levels in the blood. Insulin is produced in the pancreas. To be more specific, it's produced by the beta cells in the islets of Langerhans in the pancreas. When we eat, glucose levels rise, and insulin is released into the bloodstream. The insulin acts like a key, opening up cells so they can take in the sugar and use it as an energy source. Sugar is one of the top energy sources for the body. The body gets it in many forms, but mainly as carbohydr Continue reading >>

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