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 >>
- Exercise and Glucose Metabolism in Persons with Diabetes Mellitus: Perspectives on the Role for Continuous Glucose Monitoring
- Postprandial Blood Glucose Is a Stronger Predictor of Cardiovascular Events Than Fasting Blood Glucose in Type 2 Diabetes Mellitus, Particularly in Women: Lessons from the San Luigi Gonzaga Diabetes Study
- Exercise and Blood Glucose Levels
Learn About Photosynthesis
Very few plants can actually trap their own food and none can go grocery shopping so plants need to make their food by themselves if they want to eat! Plants are fortunate as they are the only living organisms that can make their own food. How do they do this? They make their food by combining carbon dioxide gas that is found in air with water and nutrients that they absorb from the soil. In order to do this though they need energy which they get from sunlight. The energy from sunlight (solar energy) is used by the plant to make carbon dioxide and water react chemically together and change into glucose (food) and oxygen. This process is called photosynthesis. The word photosynthesis comes from two Greek words: photo meaning light and synthesis meaning putting together so photosynthesis means putting together with light. Carbon Dioxide(gas) + Water => sunlight => Glucose + Oxygen(gas) 6 CO2 + 12 H2O -sunlight> C6 H12 O6 + 6 H2O + 6 O2 In the process of photosynthesis plants change solar energy into chemical energy. What has the sun got to do with photosynthesis? The sun is a very powerful source of energy. People are always trying to harness it to make electricity, warm their houses, heat their water etc. Plants figured out how to use solar energy millions of years ago to make their food. They use the light energy from the sun (solar energy) and convert it into chemical energy that is stored as sugar (glucose) in the plant. Excess glucose is stored as starch in the leaves, roots, stems and seeds of the plant. The energy from the sun is transferred to the plants. This energy is then passed to animals when they eat plants. Whenever the plant needs energy it breaks down its stored glucose for its life processes Plants can do this because of leaf structures called chloropla Continue reading >>
Chapter 2 Bio Review
A pure substance that consitst entirely of one type of atom. Atoms of the same element that differ in the number of neutrons they contain. Why do all isotopes of an element have the same chemical properties? A substance formed by the chemical combination of two or more elements in definite proportions. What does the formula for table salt indicate about that compound? The structure that results when atoms are joined together by covalent bonds. What is it called when atoms share two electrons? What are slight attractions that develop between oppositely charged regions of nearby molecules? The oxygen end of the molecule has a slight negative charge and the hydrogen end has a slight positive charge. What results from the oxygen atom being at one end of a water moleucle and the hydrogen atoms being at the other end? There is an uneven distribution of electrons between the oxygen and hydrogen atoms. Attraction betweeen molecules of the same substance. Attraction between molecules of different substances It draws water out of the roots and up into the stems and leaves. Material composed of two or more elements or compounds that are physically mixed together but not chemically combined. Mixture of two or more substances in which the molecules of the substaces are evenly mixed. What is the greatest solvent in the world? Substance in which the solute dissolves in a solution. Substance that is dissolved in a solution. Mixtures of water and nondissolved material. The number of positive ions are equal to the number of negative ions. Weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH. What gives carbon the ability to form chains that are almost unlimited in length? Process by which macromolecules are formed. When monomers join toget Continue reading >>
How Is Excess Glucose Stored?
The human body has an efficient and complex system of storing and preserving energy. Glucose is a type of sugar that the body uses for energy. Glucose is the product of breaking down carbohydrates into their simplest form. Carbohydrates should make up approximately 45 to 65 percent of your daily caloric intake, according to MayoClinic.com. Video of the Day Glucose is a simple sugar found in carbohydrates. When more complex carbohydrates such as polysaccharides and disaccharides are broken down in the stomach, they break down into the monosaccharide glucose. Carbohydrates serve as the primary energy source for working muscles, help brain and nervous system functioning and help the body use fat more efficiently. Function of Glucose Once carbohydrates are absorbed from food, they are carried to the liver for processing. In the liver, fructose and galactose, the other forms of sugar, are converted into glucose. Some glucose gets sent to the bloodstream while the rest is stored for later energy use. Once glucose is inside the liver, glucose is phosphorylated into glucose-6-phosphate, or G6P. G6P is further metabolized into triglycerides, fatty acids, glycogen or energy. Glycogen is the form in which the body stores glucose. The liver can only store about 100 g of glucose in the form of glycogen. The muscles also store glycogen. Muscles can store approximately 500 g of glycogen. Because of the limited storage areas, any carbohydrates that are consumed beyond the storage capacity are converted to and stored as fat. There is practically no limit on how many calories the body can store as fat. The glucose stored in the liver serves as a buffer for blood glucose levels. Therefore, if the blood glucose levels start to get low because you have not consumed food for a period of time Continue reading >>
- Exercise and Glucose Metabolism in Persons with Diabetes Mellitus: Perspectives on the Role for Continuous Glucose Monitoring
- Postprandial Blood Glucose Is a Stronger Predictor of Cardiovascular Events Than Fasting Blood Glucose in Type 2 Diabetes Mellitus, Particularly in Women: Lessons from the San Luigi Gonzaga Diabetes Study
- Exercise and Blood Glucose Levels
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 >>
- Exercise and Glucose Metabolism in Persons with Diabetes Mellitus: Perspectives on the Role for Continuous Glucose Monitoring
- Postprandial Blood Glucose Is a Stronger Predictor of Cardiovascular Events Than Fasting Blood Glucose in Type 2 Diabetes Mellitus, Particularly in Women: Lessons from the San Luigi Gonzaga Diabetes Study
- Statin use and risk of diabetes mellitus
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 >>
Storage Forms Of Glucose In Organisms
When carbohydrates from the foods you consume are digested, glucose is the smallest molecule into which a carbohydrate is broken down. Glucose molecules are absorbed from intestinal cells into the bloodstream. The bloodstream then carries the glucose molecules throughout the body. Glucose enters each cell of the body and is used by the cell’s mitochondrion as fuel. Carbohydrates are in nearly every food, not just bread and pasta, which are known for “carbo loading.” Fruits, vegetables, and meats also contain carbohydrates. Any food that contains sugar has carbohydrates. And, most foods are converted to sugars when they are digested. Once an organism has taken in food, the food is digested, and needed nutrients are sent through the bloodstream. When the organism has used all the nutrients it needs to maintain proper functioning, the remaining nutrients are excreted or stored. You store it: Glycogen Animals (including humans) store some glucose in the cells so that it is available for quick shots of energy. Excess glucose is stored in the liver as the large compound called glycogen. Glycogen is a polysaccharide of glucose, but its structure allows it to pack compactly, so more of it can be stored in cells for later use. If you consume so many extra carbohydrates that your body stores more and more glucose, all your glycogen may be compactly structured, but you no longer will be. Starch it, please: Storing glucose in plants The storage form of glucose in plants is starch. Starch is a polysaccharide. The leaves of a plant make sugar during the process of photosynthesis. Photosynthesis occurs in light (photo = light), such as when the sun is shining. The energy from the sunlight is used to make energy for the plant. So, when plants are making sugar (for fuel, energy) o Continue reading >>
When Does A Plant Change Sugar To Starch?
Plant photosynthesis and energy creation are complex processes involving carbon dioxide, water and sunlight, facilitated by multiple enzymes to create the basic sugar called glucose. Much of the glucose plants produce is immediately metabolized into different forms of energy that plants use to grow and reproduce. The portions of glucose that are not immediately converted to energy are converted to complex sugar compounds, called starches. These are produced after the photosynthesis cycle. Plants then store starches for future energy needs or use them to build new tissues. Photosynthesis Plants are photoautotrophs. Unlike humans and animals, they create their own energy from sunlight and naturally occurring organic compounds. Photosynthesis is the process by which plants use light energy to create glucose by reacting this energy, in the form of electrons, with water and carbon dioxide in cell membranes. Glucose is then used during cellular metabolism in plant tissues to create energy. When sunlight is ample, plants often create more glucose than is needed for immediate metabolism and store it in starches. Starches Plants store starches in a variety of ways. Starch molecules are enormous when compared to other simple molecules, often containing thousands of bonded sugars. Photosynthesis is carried out in plant cells and requires two distinct processes known as light dependent and light independent reactions. Both most occur for glucose to be synthesized. Thus, plants build starches only after the metabolic processes of photosynthesis. Enzymes bond glucose molecules into more complex sugars that form starches. Storing Starches Plants create, use and store starches for many purposes, but the two major ones are cellulose synthesis and energy storage. Cellulose is the primary Continue reading >>
Is Glucose Stored In The Human Body?
Glucose is a sugar that serves as a primary energy source for your body. It also provides fuel for optimal brain and nervous system activity, which may help support cognitive functions such as learning and memory. The human body stores glucose in several forms to meet immediate and future energy requirements. Video of the Day Glucose is not present in food sources. Instead, your body converts carbohydrates from foods into glucose with the help of amylase, an enzyme produced by your saliva glands and pancreas. Carbohydrates are found in all plant-based foods -- grains and starchy vegetables such as corn and potatoes are particularly abundant in carbohydrates. Beans, vegetables, seeds, fruits and nuts also supply carbohydrates. Dairy products are the only animal-based foods that contain this nutrient. As you body breaks down carbohydrates into glucose, it delivers it to your bloodstream to supply your body's cells with fuel for energy. Insulin, which is produced by your pancreas, aids in the transfer of glucose through cell walls. Unused glucose is converted to glycogen by a chemical process called glycogenesis, and is stored in muscle tissues and your liver. Glycogen serves as a backup fuel source when blood glucose levels drop. Your liver and muscles can only store a limited amount of glycogen. If your bloodstream contains more glucose than your body can store as glycogen, your body stores excess glucose as fat cells. Like glycogen, fat is stored for future energy; however, glucose storage as fat can contribute to weight gain and obesity. Obesity is a risk factor for diabetes and heart disease, and can increase strain on your bones and joints. Your body must store glucose in your bloodstream before converting and storing it as glycogen or fat. Excess glucose in your blo Continue reading >>
What Part Of Plant Can Store Extra Food As Sugar Or Starch?
Healthy plants tend to create much more food than they can immediately use. The excess food is stored as sugars and starches in various parts of the plants. These stores provide a source of energy not only for the plants, but also for the animals and humans that eat them. Plant Foods Carbohydrates are the simplest types of foods manufactured and stored by plants. Sugar and starch are two types of carbohydrates. Plant food is made in the leaves, where the green compound chlorophyll absorbs energy from the sun in a process called photosynthesis. Glucose Glucose is a simple sugar that is stored in large quantities in the stems of some plants. One example is the thick stems of the corn plant. Fructose Fructose is another simple sugar. Its chemical composition is slightly different from that of glucose and usually is stored in fruit. For this reason, it commonly is called fruit sugar. Complex Sugars Some plants, such as sugar cane and sugar beets, are very efficient at creating and storing complex sugars. These plants take the simple sugars, glucose and fructose, and create a higher form of sugar that is stored in either the stems, such as in the cane, or the roots, as in the sugar beet. Starch Starch is a common reserve food in green plants. Unlike sugars, which are soluble in water, starches must be digested before being usable. Starch is stored in grains, such as in rice or wheat plants. Starches are an important staple in the human diet. Fun Fact The onion bulb that we eat is actually made up of leaves that are specially designed to store water and food sugars underground. Continue reading >>
How Can A Plant Use The Sugars Made In Photosynthesis?
How can a plant use the sugars made in photosynthesis? During the process of photosynthesis, plants utilize sunlight and convert it into useful products, according to the following well-balanced chemical equation: `6CO_2 + 6H_2O + sunlight -> C_6H_12O_6 + 6O_2` In this reaction, glucose (a common sugar) is produced. These glucose molecules are used by the plant in a number of ways. The most common use is the production of energy (in the form of ATP molecules) through the process of cellular respiration. This process... During the process of photosynthesis, plants utilize sunlight and convert it into useful products, according to the following well-balanced chemical equation: `6CO_2 + 6H_2O + sunlight -> C_6H_12O_6 + 6O_2` In this reaction, glucose (a common sugar) is produced. These glucose molecules are used by the plant in a number of ways. The most common use is the production of energy (in the form of ATP molecules) through the process of cellular respiration. This process can be summarized by the following equation: `C_6H_12O_6 + 6O_2 -> 6CO_2 + 6H_2O + ATP` Note that most of the processes require energy, including the process of photosynthesis. During the daytime hours, when photosynthesis is taking place, plants produce more glucose than they can consume. This extra glucose is stored in the plant in the form of starch. Cell walls are made up of starch and that is where much of the extra glucose is used. Sugars are also stored in other parts of the plant. Apart from starch, sugars can be also be stored as fats and oils. Glucose can also be converted to sucrose and stored in fruits, stem, roots, seeds, etc. Glucose can also be used in the formation of amino acids, which are then used for protein synthesis in the plants. Plants are made of eukaryotic cells that con Continue reading >>
How Do Plants Store Excess Sugar?
All living organisms are formed from units called cells. All cells contain DNA to create other cells. The cells are semipermeable, which means they allow some substances to get through the membrane and deny others access. Plant cells are a bit more complex. They have internal sub-sections known as organelles and micro-fibers that form a cytoskeleton in a nucleus bound to the membrane which contains DNA. Unused sugars in plants are stored as starch. Starch is considered to be a complex sugar. The cell wall of a plant has a barrier that the membrane presses against and that it uses to maintain a rigid structure. Inside of the plant, excess sugar is stored as starch. Starches are recognized as a major component of foods ingested into the human body, to be used as energy or stored as fat. Likewise, the plant uses these starches as stored food sources. In woody plant stems, starch is also stored for later use as energy. Trees are known to create sugar through photosynthesis; the unused sugar is transported through the phloem, stored in the trunk or roots as starch and then turned back into sugar to be used as energy again at the start of a new spring. The glucose units in plants are linked in linear bonds. Whenever plants need energy for cell work, they hydrolyze the stored starch, releasing the glucose subunits. The strategically branched polymer of glucose used in this process is known as amylopectin; it and amylose make up the two main components of starch. Starch itself is made of at least 70% amylopectin, constituting the bulk of the plant being used for energy storage. Continue reading >>
Starch Is A Polymer Made By Plants To Store Energy.
Starch is a polymer made by plants to store energy. You see, plants need energy to grow and grow and grow. They use energy from sunlight to make a simple sugar , glucose. Plants make polymers - starch - out of extra glucose, so it's right there when they need it. Click the picture to see a 3-d interactive version of starch. Wouldn't it be great for a whole bunch of glucose molecules to be together in one package? Well, plants thought that was a cool idea. They hook glucose molecules all together in such a way that the long chain curls all around and forms a big globby polymer. That's starch! Whenever the plant needs energy, it can chomp a little glucose off of the starch. Chomp! mmmmm! Here is a short section of starch, with only 4 glucose molecules. Starch can also have a lot of branches. Each branch is a short chain made from glucoses, and each branch can make more branches. Crazy, huh? Another good thing about starch: Each little glucose likes to have water all around it. That can be really hard on the plant. In a starch polymer, the glucose units have other glucose units around them, and that works just as well as water. So, the plant doesn't need so much water, and everybody's happy! We need glucose for energy, too. You even need energy to think! When you eat starchy food, special proteins called enzymes (which are also polymers, by the way) break starch down into glucose, soyour body can burn it for energy. This starts happening right in your mouth! There's an enzyme in your spit (yep, your spit!) that starts to cut up the starch. Check out this link to see how you can taste this enzyme working. Foods that have a lot of starch include: grains (like rice and wheat), corn, and potatoes. Our bodies can't make starch - only plants make starch. We have two ways of sto Continue reading >>
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 >>
Carbohydrates
Sugars and starches are important carbohydrates that we take in often. Carbohydrates provide a great part of the energy in our diets. Foods rich in carbohydrates, including potatoes, bread, and maize, are usually the most abundant and cheapest when compared with foods high in protein and fat content. Carbohydrates are burned during body processes to produce energy, giving out carbon dioxide and water. Starches are found mainly in grains, legumes, and tubers, and sugars are found in plants and fruits. Sugars are the smallest units of carbohydrates, and when they join together, they form starch. Role of Carbohydrates The main role of carbohydrates in our diet is to produce energy. Each gram of carbohydrates provides us with about four calories. Carbohydrates also act as a food store. Our bodies also store carbohydrates in insoluble forms as glycogen or starch. This is because these two carbohydrates are compact. Carbohydrates are also combined with nitrogen to form non-essential amino acids. In plants, carbohydrates make up part of the cellulose, giving plants strength and structure. How are Carbohydrates Made? Plants can make their own food because they have chlorophyll in their green leaves. They make food in a process known as photosynthesis. The process of photosynthesis is essential for all living things in the world, and plants are the only food-producers, while the other animals either feed on plants or feed on other animals. For the process of photosynthesis, carbon dioxide and sunlight have to be present. Also, the plant must have water. Only then can the plant photosynthesize and produce glucose and oxygen from carbon dioxide, water and sunlight. The equation of photosynthesis is as follows: 6 CO2 + 6 H2O ---> C6H12O6 + 6 O2 Carbon dioxide + Water ---> Glucose + Continue reading >>
