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How Is Glucose Stored In Animals

Glycogen Metabolism

Glycogen Metabolism

Glycogen is a readily mobilized storage form of glucose. It is a very large, branched polymer of glucose residues (Figure 21.1) that can be broken down to yield glucose molecules when energy is needed. Most of the glucose residues in glycogen are linked by α-1,4-glycosidic bonds. Branches at about every tenth residue are created by α-1,6-glycosidic bonds. Recall that α-glycosidic linkages form open helical polymers, whereas β linkages produce nearly straight strands that form structural fibrils, as in cellulose (Section 11.2.3). Glycogen is not as reduced as fatty acids are and consequently not as energy rich. Why do animals store any energy as glycogen? Why not convert all excess fuel into fatty acids? Glycogen is an important fuel reserve for several reasons. The controlled breakdown of glycogen and release of glucose increase the amount of glucose that is available between meals. Hence, glycogen serves as a buffer to maintain blood-glucose levels. Glycogen's role in maintaining blood-glucose levels is especially important because glucose is virtually the only fuel used by the brain, except during prolonged starvation. Moreover, the glucose from glycogen is readily mobilized and is therefore a good source of energy for sudden, strenuous activity. Unlike fatty acids, the released glucose can provide energy in the absence of oxygen and can thus supply energy for anaerobic activity. The two major sites of glycogen storage are the liver and skeletal muscle. The concentration of glycogen is higher in the liver than in muscle (10% versus 2% by weight), but more glycogen is stored in skeletal muscle overall because of its much greater mass. Glycogen is present in the cytosol in the form of granules ranging in diameter from 10 to 40 nm (Figure 21.2). In the liver, glycoge Continue reading >>

Glucose

Glucose

Physiology • Glucose in the blood is derived from three main sources: ○ ▪ Glucose is the end-product of carbohydrate digestion, absorbed by enterocytes. ▪ Increased blood glucose concentrations occur 2 to 4 hours after a meal in simple-stomached animals. ○ Hepatic production ▪ Gluconeogenesis and glycogenolysis within hepatic cells produce glucose when metabolically necessary. □ Gluconeogenesis converts noncarbohydrate sources, primarily amino acids (from protein) and glycerol (from fat), in simple-stomached animals. □ Glycogenolysis converts glycogen (poly-glucose) stored in hepatocytes to glucose through hydrolysis. ▪ Gluconeogenesis and glycogenolysis within hepatic cells produce glucose when metabolically necessary. □ Gluconeogenesis converts noncarbohydrate sources, primarily amino acids (from protein) and glycerol (from fat), in simple-stomached animals. □ Glycogenolysis converts glycogen (poly-glucose) stored in hepatocytes to glucose through hydrolysis. ○ ▪ Gluconeogenesis and glycogenolysis within renal epithelial cells can result in the formation of glucose when metabolically necessary. • The plasma concentration of glucose is controlled by a number of hormones, in particular, insulin and glucagon. The physiology of glucose homeostasis is controlled primarily by insulin release in response to elevated glucose levels (postprandial), although in birds, glucagon appears to serve as the primary regulator. Significant species variations in glucose levels have been noted. In general, levels are lowest in reptiles (60 to 100 mg/dL) and highest in birds (200 to 500 mg/dL), with mammals in between (100 to 200 mg/dL). Glucose that is not needed for energy is stored in the form of glycogen as a source of potential energy, readily available whe Continue reading >>

Carbohydrates Composition: Plants Vs. Animals

Carbohydrates Composition: Plants Vs. Animals

Carbohydrates Composition: Plants vs. Animals Watch short & fun videos Start Your Free Trial Today Laura has a Masters of Science in Food Science and Human Nutrition and has taught college Science. Log in or sign up to add this lesson to a Custom Course. Custom Courses are courses that you create from Study.com lessons. Use them just like other courses to track progress, access quizzes and exams, and share content. Organize and share selected lessons with your class. Make planning easier by creating your own custom course. Create a new course from any lesson page or your dashboard. Click "Add to" located below the video player and follow the prompts to name your course and save your lesson. Click on the "Custom Courses" tab, then click "Create course". Next, go to any lesson page and begin adding lessons. Edit your Custom Course directly from your dashboard. Name your Custom Course and add an optional description or learning objective. Create chapters to group lesson within your course. Remove and reorder chapters and lessons at any time. Share your Custom Course or assign lessons and chapters. Share or assign lessons and chapters by clicking the "Teacher" tab on the lesson or chapter page you want to assign. Students' quiz scores and video views will be trackable in your "Teacher" tab. You can share your Custom Course by copying and pasting the course URL. Only Study.com members will be able to access the entire course. In this lesson, we will learn about carbohydrates in plants and animals. We will particularly learn about starch (amylopectin and amylose), cellulose, and glycogen. Have you ever wondered what happens to the carbohydrates when you eat a cracker or stalk of celery? What happens to the carbohydrates depends on the form of the carbohydrates in the plant, Continue reading >>

Role Of Carbohydrates

Role Of Carbohydrates

Life on this planet needs a constant supply of energy in order to fight the effects of entropy and the second law of thermodynamics. The most abundant source of this energy is the sun, where vast amounts of radiant energy are created in the nuclear fusion furnaces. A tiny part of this radiant energy reaches this planet in the form of light, where a tiny part, of a tiny part of this energy is absorbed by plants and converted from light energy into chemical energy. This is the process called photosynthesis. Pigments in special cellular organelles trap quanta of light energy and convert them to high energy electrons. These high energy electrons are in turn used to move electrons in covalent bonds to a higher energy state. In this process atoms and bonds in carbon dioxide and water are rearranged and new molecules are created. Quanta of light energy are used to pull electrons in covalent bonds to higher energy levels where they are stable and stored for future use. Two important molecular products are produced in this process; oxygen, which is released into the atmosphere, and 3-phosphoglyceric acid, which is kept inside the cells. All plants create 3-phosphoglyceric acid (3PG) as the first stable chemical molecule in this energy trapping mechanism. This simple, 3-carbon molecule is then used to make all the other kinds of carbohydrates the plant needs. Monosaccharide sugars are made by combining and recombining all those carbon atoms first trapped as 3PG. The most abundant and versatile of these monosaccharides is glucose. This versatile molecule then plays many roles in the life of the plant - and the lives of animals that eat them. A primary role for the glucose molecule is to act as a source of energy; a fuel. Plants and animals use glucose as a soluble, easily distribu Continue reading >>

Timeis

Timeis

Home Technology Technology Trends Trends in Agriculture Food Storage Strategies in Plants and Animals How do people store food? Dry seeds like wheat, barley and pulses are kept free of moisture, they can be stored for long time. Even some animals do this. Honey bees store nectar, squirrels stock up nuts in autumn. One particular method of storing food is the only means available to most animals. Eat the food whenever it is available, and store it as fat inside the body, which is safe in the adipose tissues. For many animals finding continuous food supply is very difficult, so storing enough nutrients and energy inside their won body is essential. And for the animals that hibernate in long winter when no food is available, eating fat in autumn is the only way to survive from year to year. In green plants food is only supplied through photosynthesis that requires only light water and carbon dioxide for preparation of their food. Storing food reserves is not a problem in the plants growing in temperature, water, etc are always available. But deciduous plant growing in temperate and hot regions drop which drop their leaves and become dormant in adverse conditions are similar to animals in that need to have stored food to maintain their life cycle while leafless. If a plant had no nutrient reserve inside his body when it dropped its leaves, it would not even be able to make new leaves on the onset if spring. It will die. We and animals store our reserve energy as fats. Our adipose tissues are located in different part of our body as stomach, arms legs, etc. A little bit of energy is stored as glycogen, present in our muscle cells and liver, but that is only enough to keep us going for a few hours as any runner or cyclist knows. The long-term energy storage compound is fat. Continue reading >>

Carbohydrates - Why Do Animals Use Glycogen For Their Polysaccharide Storage Whereas Plants Use Starch? - Biology Stack Exchange

Carbohydrates - Why Do Animals Use Glycogen For Their Polysaccharide Storage Whereas Plants Use Starch? - Biology Stack Exchange

Why do animals use glycogen for their polysaccharide storage whereas plants use starch? The polysaccharide storage form of glucose in animals is glycogen, whereas in plants it is starch. Both of these are polymers of -glucose with -l,4 glycosidic linkages and -l,6 glycosidic branch points (Wikipedia article on polysaccharides ). The only difference that most sources mention (e.g. Berg et al. is that glycogen contains more branches than starch. It is not clear to me from this information what effect the different branching would have on the structures of the polysaccharides, nor why one rather than the other would be preferred in animals and plants. It is surprisingly difficult to find a proper answer to this question on the internet my own answer was only found after consulting specialized reviews. I therefore think this is an important question and have therefore edited it, tightening up the wording, avoiding the implication that polysaccharides are the only storage form, and spelling out the chemistry. If the original poster is still active on the list I hope he will accept these changes. David Jan 9 at 17:30 What about fungi? Do they even have storage polysaccharides and if so, what kind? jaia Jan 12 at 2:03 well glycogen can be broken down into sugars a lot faster , many more branches means many more ends to clip individual sugars off of, that's how you mobilize the sugar for use, it is clipped of the end of a strand. With many more branches glycogen can mobilize more sugar more quickly. This is not important in plants but in animals that need to be able mobilize lots of energy in a hurry, glycogen works better. Additionally glycogen is a smaller molecule and easier to make, not surprising since glycogen is the ancestral condition for plants and animals. As for why Continue reading >>

Carbohydrates - Glycogen

Carbohydrates - Glycogen

Polysaccharides are carbohydrate polymers consisting of tens to hundreds to several thousand monosaccharide units. All of the common polysaccharides contain glucose as the monosaccharide unit. Polysaccharides are synthesized by plants, animals, and humans to be stored for food, structural support, or metabolized for energy. Glycogen is the storage form of glucose in animals and humans which is analogous to the starch in plants. Glycogen is synthesized and stored mainly in the liver and the muscles. Structurally, glycogen is very similar to amylopectin with alpha acetal linkages, however, it has even more branching and more glucose units are present than in amylopectin. Various samples of glycogen have been measured at 1,700-600,000 units of glucose. The structure of glycogen consists of long polymer chains of glucose units connected by an alpha acetal linkage. The graphic on the left shows a very small portion of a glycogen chain. All of the monomer units are alpha-D-glucose, and all the alpha acetal links connect C # 1 of one glucose to C # 4 of the next glucose. The branches are formed by linking C # 1 to a C # 6 through an acetal linkages. In glycogen, the branches occur at intervals of 8-10 glucose units, while in amylopectin the branches are separated by 12-20 glucose units. Continue reading >>

Glycogen

Glycogen

Schematic two-dimensional cross-sectional view of glycogen: A core protein of glycogenin is surrounded by branches of glucose units. The entire globular granule may contain around 30,000 glucose units.[1] A view of the atomic structure of a single branched strand of glucose units in a glycogen molecule. Glycogen (black granules) in spermatozoa of a flatworm; transmission electron microscopy, scale: 0.3 µm Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in humans,[2] animals,[3] fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body. Glycogen functions as one of two forms of long-term energy reserves, with the other form being triglyceride stores in adipose tissue (i.e., body fat). In humans, glycogen is made and stored primarily in the cells of the liver and skeletal muscle.[2][4] In the liver, glycogen can make up from 5–6% of the organ's fresh weight and the liver of an adult weighing 70 kg can store roughly 100–120 grams of glycogen.[2][5] In skeletal muscle, Glycogen is found in a low concentration (1–2% of the muscle mass) and the skeletal muscle of an adult weighing 70 kg can store roughly 400 grams of glycogen.[2] The amount of glycogen stored in the body—particularly within the muscles and liver—mostly depends on physical training, basal metabolic rate, and eating habits. Small amounts of glycogen are also found in other tissues and cells, including the kidneys, red blood cells,[6][7][8] white blood cells,[medical citation needed] and glial cells in the brain.[9] The uterus also stores glycogen during pregnancy to nourish the embryo.[10] Approximately 4 grams of glucose are present in the blood of humans at all times;[2] in fasted individuals, blood glucos Continue reading >>

Biology Unit #2 Flashcards | Quizlet

Biology Unit #2 Flashcards | Quizlet

Why are carbon atoms so common in living things? One of the most abundant hydrocarbons in natural gass? 4 groups that are functional and organic? Hydroxyl, Carbonyl, Carboxyl, Amino group 3 shapes the carbon backbones of organic molecules can take? What determines the properties of a functional group? The carbon skeleton and the attached functional group Using the dehydration reaction, cells construct what from 2 monosaccharides? How meany monomers are polymers built from? What 4 classes are life's largest molecules classified into? Carbohydrates, lipids, proteins, nucleic acids Each time a monomer is added to a chain, what is released? How do cells break bonds between monomers? What's the connection between monomers and polymers? Many monomers linked together make polymers What molecule is released during the construction of a polymer? What is this reaction called? What are two things that carbohydrates provide? What's at the core of most sugar molecules found in nature? What molecule is the main fuel supply for cellular work? What happens to glucose molecules that are not used immediately? Incorporated into larger carbohydrates, used to make fat molecules A glucose molecule linked to a fructose molecule Long polymer chains made up of simple sugar monomers A polysaccharide found in plant cells that consists entirely of glucose monomers What happens when plants break down starch molecules? How do animals and humans store excess sugar? In the form of a polysaccharide called glycogen What polysaccharide in plants serve as building materials? What benefit does plants get from cellulose? Protects cells, stiffens plant preventing it from flopping over Why are almost all carbohydrates hydrophilic? What's the difference between a monosaccharide and a polysaccharide? A monosac Continue reading >>

Glycogen Vs. Glucose

Glycogen Vs. Glucose

Lexa W. Lee is a New Orleans-based writer with more than 20 years of experience. She has contributed to "Central Nervous System News" and the "Journal of Naturopathic Medicine," as well as several online publications. Lee holds a Bachelor of Science in biology from Reed College, a naturopathic medical degree from the National College of Naturopathic Medicine and served as a postdoctoral researcher in immunology. A bowl of colored pasta.Photo Credit: AlexPro9500/iStock/Getty Images Glucose and glycogen are both carbohydrates, but glucose is classified as a monosaccharide and sugar. As a single unit, it is a much smaller molecule. According to Virtual Chembook at Elmhurst College, glycogen is classified as a complex carbohydrate and starch, and it's made up of several glucose molecules. Glucose can be rapidly metabolized to produce energy. It dissolves readily in water and can be readily transported throughout your body. It can be carried in your bloodstream as well as in the sap of plants. Glucose serves as a primary energy source for plants as well as animals. Joining different numbers of glucose units forms different types of carbohydrates, according to the Department of Chemistry at Imperial College in the U.K. Disaccharides like sucrose and lactose consist of two linked glucose units, while polysaccarides consist of many more. In animals, glycogen is a large storage molecule for extra glucose, just as starch is the storage form in plants. Your liver and muscles synthesize glycogen and act as your main storehouses. Your stores can be broken down again to glucose for energy if necessary, and they can also provide structural support in various tissues in your body. One glycogen molecule can consist of long chains of 1,700 to 600,000 glucose units. About 0.5 percent of Continue reading >>

Glucose Storage In People

Glucose Storage In People

Now, all you wiseacres out there probably said on the shelf, or in a jar - and I guess that could answer the question! But how does your BODY (or Monomer Mouse's little body) store glucose so that it can get to it fast and easy for quick energy? We make a polymer called glycogen, which is a lot like starch. It's made out of repeating glucose units put together just like starch, and it has a lot of branches - (more than starch does). Like starch, glycogen curls around and forms a big globby structure. Because it's branched and globby, glycogen has ends sticking out all over. Enzymes can attach onto those ends and break the glycogen down fast into glucose units, that can be broken down further (by a bunch of other enzymes) to make ENERGY! So, where would you expect glycogen to be? Where you need it the most - in your muscles so you can run fast with a burst of energy. (Glycogen is also in your liver.) Glycogen is really short-term storage. For long-term storage of energy, your body turns that glucose into fat. Fat is a pretty big molecule, but it's not a polymer. Fat can be stored compactly in special cells (called adipose) because it doesn't dissolve in water - it forms droplets in special compartments in adipose cells. So there you go! That's how your body stores energy. When you eat starch, your body breaks it down into glucose, then makes glycogen for short-term storage. If there's a bunch left over that's not needed, fat is made for long-term storage. Content by Patricia DePra; Graphics by Virginia Smith. Continue reading >>

Storage And Use Of Glucose

Storage And Use Of Glucose

The glucose produced in photosynthesis may be used in various ways by plants and algae. Storage Glucose is needed by cells for respiration. However, it is not produced at night when it is too dark for photosynthesis to happen. Plants and algae store glucose as insoluble products. These include: Use Some glucose is used for respiration to release energy. Some is used to produce: Plants also need nitrates to make proteins. These are absorbed from the soil as nitrate ions. Three factors can limit the speed of photosynthesis: light intensity, carbon dioxide concentration and temperature. Without enough light, a plant cannot photosynthesise very quickly, even if there is plenty of water and carbon dioxide. Increasing the light intensity will boost the speed of photosynthesis. Sometimes photosynthesis is limited by the concentration of carbon dioxide in the air. Even if there is plenty of light, a plant cannot photosynthesise if there is insufficient carbon dioxide. If it gets too cold, the rate of photosynthesis will decrease. Plants cannot photosynthesise if it gets too hot. If you plot the rate of photosynthesis against the levels of these three limiting factors, you get graphs like the ones above. In practice, any one of these factors could limit the rate of photosynthesis. Farmers can use their knowledge of factors limiting the rate of photosynthesis to increase crop yields. This is particularly true in greenhouses, where the conditions are more easily controlled than in the open air outside: The use of artificial light allows photosynthesis to continue beyond daylight hours. Bright lights also provide a higher-than-normal light intensity. The use of artificial heating allows photosynthesis to continue at an increased rate. The use of additional carbon dioxide released i Continue reading >>

Biology Dna & Molecules

Biology Dna & Molecules

What experiment did Frederick Griffiths conduct? The mouse experiment when he injected live disease causing bacteria (smooth colonies) that killed mice when he injected it into them. When he injected the harmless bacteria (rough colonies), the mouse lived. Then he killed the live bacteria (smooth colonies) by putting it over heat and the mouse lived. Lastly, he combined the heat killed smooth colonie and the rough harmless colonie and the mouse died. What did Griffiths conclude after his experiment was completed? That something must be "transforming" those bacteria. He re-did Griffith's experiment, but what he did differently was add enzymes that killed protein, lipids, carbs, and nucleic acids (DNA & RNA). What was the results of Avery's experiment? The experiment only worked when the DNA was intact. How many bonds does each of those things have? Hydrogen - 1, Oxygen - 2, Nitrogen - 3, Carbon - 4 What does the number of protons in a neutral atom equal? how do you figure out the number of neutrons? A bunch of the same compounds strung together (many parts) Weak bonds, easily broken (and easily put back together). They have positive and negative ends and a positive end sticks to the negative end of another molecule. They are strong bonds (they can be broken, but they are harder to break than hydrogen bonds and they come from sharing electrons) Are almost all lipids hydrophobic or hydrophilic? Are almost all carbohydrates hydrophobic or hydrophilic? It is a monomer of the polymer cellulose and glycogen Structural support, energy storage, and information transport How many amino acids are the monomers of polypeptides? Does the shape of a protein significantly affect its function? What is the polymer shape and function determined by? the type of monomer that is used to bui Continue reading >>

Glucose

Glucose

Previous (Glucagon) Next (Glutamic acid) Chemical name 6-(hydroxymethyl)oxane-2,3,4,5-tetrol Glucose (Glc) is a monosaccharide (or simple sugar) with the chemical formula C6H12O6. It is the major free sugar circulating in the blood of higher animals, and the preferred fuel of the brain and nervous system, as well as red blood cells (erythrocytes). As a universal substrate (a molecule upon which an enzyme acts) for the production of cellular energy, glucose is of central importance in the metabolism of all life forms. It is one of the main products of photosynthesis, the process by which photoautotrophs such as plants and algae convert energy from sunlight into potential chemical energy to be used by the cell. Glucose is also a major starting point for cellular respiration, in which the chemical bonds of energy-rich molecules such as glucose are converted into energy usable for life processes. Glucose stands out as a striking example of the complex interconnectedness of plants and animals: the plant captures solar energy into a glucose molecule, converts it to a more complex form(starch or cellulose) that is eaten by animals, which recover the original glucose units, deliver it to their cells, and eventually use that stored solar energy for their own metabolism. Milk cows, for example, graze on grass as a source of cellulose, which they break down to glucose using their four-chambered stomachs. Some of that glucose then goes into the milk we drink. As glucose is vital for the human body and for the brain, it is important to maintain rather constant blood glucose levels. For those with diabetes mellitus, a disease where glucose levels in the blood get too high, personal responsibility (i.e. self management) is the key for treatment. For diabetes there is usually a complex Continue reading >>

Glucose

Glucose

Because Glucose is the unit from which starch, cellulose and glycogen are made up, and because of its special role in biological processes, there are probably more glucose groups in Nature than any other organic group. It is extremely important in Nature as one of the main energy sources for living organisms, both in plants and animals. Glucose was first isolated in 1747 from raisins by Andreas Marggraf. The name glucose was coined in 1838 by Jean Dumas, from the greek glycos, sugar or sweet), and the structure was discovered by Emil Fischer around the turn of the century. In fact, there are 2 forms of glucose, the dextrose). In fact, the full name for common glucose is D-(+)-glucose, and its chemically correct name (using the IUPAC systematic naming system for organic molecules) is (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanol! Glucose can be thought of as a derivative of hexane (a 6-carbon chain) with -OH groups attached to every carbon except the endmost one, which exists as an aldehyde carbonyl. However because the chain is flexible it can wrap around until the 2 ends react together to form a ring structure. Thus a solution of glucose can be thought of as a rapidly changing mixture of rings and chains, continually interconverting between the 2 forms. Glucose is a ready source of energy, since its carbon atoms are easily oxidised (burnt) to form carbon dioxide, releasing energy in the process. However, unlike other hydrocarbon fuels, which are insoluble in water, the numerous OH groups in glucose allow it to readily hydrogen-bond with water molecules, so making it highly soluble in water. This allows the glucose fuel to be transported easily within biological systems, for example in the bloodstream of animals or the sap of plants. In fact the average adult has 5-6 gra Continue reading >>

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