Multiple Choice Quiz 1
(See related pages) 1 Which one of the following would not be a nutrient? 2 Most vitamins, minerals, and water all have this in common: 3 When the body metabolizes nutrients for energy, fats yield about _______ times the energy as carbohydrates or proteins. 4 A calorie is the amount of energy necessary to raise the temperature of one gram of _________ one degree __________. 5 One piece of apple pie would yield about 6 The disaccharide that most people think of as table sugar is 7 When lactose is digested, it yields two monosaccharides called 8 The complex carbohydrate (polysaccharide) that is digested to the monosaccharide, glucose, and is found in vegetables, fruits, and grains and is called 9 If excess glucose is present in the body, the glucose first will be stored as __________ in muscle and the liver. 10 Triglycerides that contain one or more double covalent bonds between carbon atoms of their fatty acids are called 11 Bubbling hydrogen gas through polyunsaturated vegetable oil will cause the oil to become more 12 The lipid that is a component of the plasma membrane and can be used to form bile salts and steroid hormones is 13 The American Heart Association recommends that saturated fats should contribute no more than 10% of total fat intake. Excess fats, especially cholesterol and saturated fat, can increase the risk of 16 The daily-recommended consumption amount of protein for a healthy adult is about _____% of total kilocalorie intake per day. 20 Inorganic nutrients that are necessary for normal metabolism are called 23 When a molecule loses an electron, that molecule is said to be ___________ and often a(n) _____________ ion is lost along with the electron. 25 When a hydrogen ion and an associated electron are lost from a nutrient molecule, which of the followi Continue reading >>
Glycemic Load And Glycemic Index: What’s The Difference And Why Does It Matter?
A few months ago I wrote about using the glycemic index (GI) ranking to manage weight and diabetes. Another measurement many use for weight and blood sugar management is Glycemic Load (GL). I was confused about the difference between these two systems so I spoke with registered dietitian and certified diabetes educator, Weiner, who straightened me out. This information may help you too. (Editor’s note: People with diabetes should speak to a qualified physician before starting a new diet.) Q: What is glycemic load in very simple terms? Susan Weiner: Glycemic load is a ranking system for carbohydrate-rich food that measures the amount of carbohydrates in a serving of food. Foods with a glycemic load (GL) under 10 are considered low-GL foods and have little impact on your blood sugar; between 10 and 20 moderate-GL foods with moderate impact on blood sugar, and above 20 high-GL foods that tend to cause blood sugar spikes. Q: How is glycemic load related to glycemic index? SW: The glycemic index indicates how rapidly a carbohydrate is digested and released as glucose (sugar) into the blood stream. In other words, how quickly foods break down into sugar in your bloodstream. A food with a high GI raises blood sugar more than a food with a medium to low GI. But the glycemic index does not take into account the amount of carbohydrate in a food. So glycemic load is a better indicator of how a carbohydrate food will affect blood sugar. Q: If a food has a high glycemic index and a low glycemic load — like graham crackers have a GI of 74 and a GL of 8.1 — how will that affect your blood sugar? SW: Food ranked high on the GI may represent a huge portion of a food because GI is not based on standard serving sizes. Basically, if a food is ranked high on the glycemic index it has Continue reading >>
4 Glucose metabolism: an example of integration of signalling pathways 4.1 Glucose metabolism We are now in a position to draw together the major concepts and components of signalling, and show how they operate in one well-understood system, namely the regulation of the storage or release of glucose in the human body. From this, you will be able to recognize archetypal pathways represented in specific examples, you will be able to appreciate how the same basic pathways can be stimulated by different hormones in different tissues, and you will see how opposing hormones activate separate pathways that affect the same targets but in opposite ways. Following a meal, insulin is released into the bloodstream by pancreatic β cells. The overall systemic effects of insulin are to increase uptake of blood glucose into cells, and to promote its storage as glycogen in muscle and liver cells. (Note that glycogen is a polysaccharide consisting of repeated units of glucose used for shortterm energy storage by animal cells.) A rise in the concentration of blood glucose, such as that following the consumption of food, stimulates insulin production, which signals through the insulin RTK. The insulin RTK phosphorylates various substrate proteins, which link to several key signalling pathways such as the Ras–MAP kinase pathway. There are, however, two major pathways that control glycogen synthesis and breakdown in animal cells (Figure 47). Figure 47 The control of glycogen synthesis by insulin. Several proteins bind, and are phosphorylated by, the activated insulin receptor. Cbl activates a pathway that is implicated in the translocation of the glucose transporter GLUT4 to the membrane, allowing glucose transport into the cell. Meanwhile, IRS-1 serves as a docking protein for PI 3-kinas Continue reading >>
Is It Possible To Improve A Diabetic Condition? What Is The Cause Of Diabetes And What Can Be Done About It.
For a simple explanation regarding Diabetic Nerve Pain 1) What is Diabetes? 2) Types of Diabetes 3) Side effects of too much sugar in the blood 4) Side effects of too much insulin 5) Diabetic Symptoms 6) 12 Signs of Diabetes 7) Complementary Natural Treatment for Diabetes What is Diabetes? Glucose is a simple sugar which serves as the body's fuel to produce heat and energy. When food is eaten and digestion occurs, the food is broken down into simple glucose molecules which then circulate in the blood to the cells where it can be used. When it is found in the human bloodstream it is referred to as "blood sugar". Carbohydrates are long chains of glucose molecules which are broken down to glucose. How does this become the condition known as diabetes? Glucose cannot penetrate the cell wall unless it is attached to molecules of insulin. The sugars and starches you eat are converted to glucose, which enters your bloodstream to be transported to the cells. This is where insulin comes in. It "unlocks" your cell walls so the glucose can enter. Insulin's job is to push the blood sugar into the cells. In order for this to work, your cells need to be sensitive to insulin. Without this, the glucose does not enter the cells but accumulates in the blood and circulates helplessly, eventually entering the kidneys and then the bladder for excretion in the urine. When your cells aren't sensitive to insulin, your body has to do something with the glucose. It converts some of it into fat, and the rest can become AGEs (advanced glycation end products) -- which can build up in the tissues, and affect cellular function. While circulating, this excess sugar will react with oxygen to form unstable molecules called free radicals which can cause havoc by stealing electrons from your body's healthy Continue reading >>
- Can Diabetes Be Reversed? Study Claims Weight Loss And Cutting Calories Cure Condition, Even In Long-Term Patients
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What Is The Role Of Glucose In Aerobic Respiration?
During aerobic respiration, cells obtain energy in the presence of oxygen through a series of reactions known as the citric acid cycle. Glucose provides a key reaction intermediate necessary for these reactions to occur. Glucose is a six-carbon sugar molecule that gets broken down into two three-carbon pyruvate molecules. These pyruvate molecules, in the presence of oxygen, can enter the citric acid cycle, producing a significant amount of energy for the cell. Glucose can be obtained directly from the diet or by the breaking down of glycogen, a polymer of glucose molecules. During glycolysis, glucose is metabolized by the cell to produce energy. Glycolysis is not very efficient in terms of energy production, but the process itself generates a series of intermediates that can be used for other processes. One such intermediate is pyruvate. In the absence of oxygen, pyruvate can be converted to lactic acid or alcohol through a process known as fermentation. However, in the presence of oxygen, during aerobic respiration, pyruvate can enter the citric acid cycle. The Citric Acid Cycle The citric acid cycle is a series of reactions that ultimately produce a significant amount of energy for the cell. This cycle can only occur under aerobic conditions -- that is, conditions in which sufficient oxygen is present. In the presence of oxygen, the pyruvate molecules formed at the end of glycolysis can enter the citric acid cycle by reacting with a compound called Acetyl-CoA. During this reaction, carbon dioxide is released. In fact, carbon dioxide is released in a number of steps during the citric acid cycle. This is, in part, an explanation of why aerobic respiration involves breathing in oxygen and breathing out carbon dioxide. Electron Transport Chain By definition, aerobic respi Continue reading >>
Will Carbs Make You Fat?
"Carbs make you fat!", "Cut carbs and you'll lose weight!", "If you eat carbs after 6 you'll get fat!". I hear statements like these an awful lot. Too often. Thrown around like facts, they're so commonplace now that a large amount of the general public have developed a phobia of carbohydrates, despite not really knowing what they are or what they do for your body. What are carbs & their function Things might get a little sciencey here - but not too much, I promise. The definition of a carbohydrate is: "a biological molecule consisting of carbon, hydrogen & oxygen atoms. Practically speaking though: tasty food like potatoes, rice, pasta, bread, biscuits, fruit, sweets.... Carbs, be they wholegrain, organic quinoa or Haribo Tangfastics, are broken down in to glucose. Glucose provides your body & brain with energy. Where quinoa & tangfastics differ is: 1) the nutrients they contain and 2) how they're broken down by your body. Both will ultimately end up as glucose; the difference between the two is the chemical structure - how quickly the CHO molecule is broken down and the sugar is absorbed and digested. Tangfastics are simple carbs, broken down quickly and released into the bloodstream whilst quinoa is complex and is released over time. Carbohydrates contain 4 calories per gram. Carbs are your body's main source of energy and so your "requirements" will vary depending on your activity levels. If you're sedantry, sitting at your desk all day typing & sitting on your arse all night watching back to back Netflix, chances are you don't need 300g of carbs to fuel you. However if you're active, either through deliberate exercise (training) or through your lifestyle (work/hobbies) then you'll need a higher level or carbs to ensure you've got the energy for optimal performance. Continue reading >>
Not to be confused with Glycogenesis or Glyceroneogenesis. Simplified Gluconeogenesis Pathway Gluconeogenesis (GNG) is a metabolic pathway that results in the generation of glucose from certain non-carbohydrate carbon substrates. From breakdown of proteins, these substrates include glucogenic amino acids (although not ketogenic amino acids); from breakdown of lipids (such as triglycerides), they include glycerol (although not fatty acids); and from other steps in metabolism they include pyruvate and lactate. Gluconeogenesis is one of several main mechanisms used by humans and many other animals to maintain blood glucose levels, avoiding low levels (hypoglycemia). Other means include the degradation of glycogen (glycogenolysis) and fatty acid catabolism. Gluconeogenesis is a ubiquitous process, present in plants, animals, fungi, bacteria, and other microorganisms. In vertebrates, gluconeogenesis takes place mainly in the liver and, to a lesser extent, in the cortex of the kidneys. In ruminants, this tends to be a continuous process. In many other animals, the process occurs during periods of fasting, starvation, low-carbohydrate diets, or intense exercise. The process is highly endergonic until it is coupled to the hydrolysis of ATP or GTP, effectively making the process exergonic. For example, the pathway leading from pyruvate to glucose-6-phosphate requires 4 molecules of ATP and 2 molecules of GTP to proceed spontaneously. Gluconeogenesis is often associated with ketosis. Gluconeogenesis is also a target of therapy for type 2 diabetes, such as the antidiabetic drug, metformin, which inhibits glucose formation and stimulates glucose uptake by cells. In ruminants, because dietary carbohydrates tend to be metabolized by rumen organisms, gluconeogenesis occurs Continue reading >>
Role Of Glucose In Cellular Respiration
This lesson is on the role of glucose in cellular respiration. In this lesson, we'll explain what cellular respiration is and what we need to start with to get the end products. We'll specifically look at the importance of glucose in this process. What Is Cellular Respiration? Sugar is everywhere in our world, from packaged foods in our diet, like tomato sauce, to homemade baked goods, like pies. In fact, sugar is even the main molecule in fruits and vegetables. The simplest form of sugar is called glucose. Glucose is getting a bad rap lately and many people are cutting sugar out from their diet entirely. However, glucose is the main molecule our bodies use for energy and we cannot survive without it. The process of using glucose to make energy is called cellular respiration. The reactants, or what we start with, in cellular respiration are glucose and oxygen. We get oxygen from breathing in air. Our bodies do cellular respiration to make energy, which is stored as ATP, and carbon dioxide. Carbon dioxide is a waste product, meaning our bodies don't want it, so we get rid of it through exhaling. To start the process of cellular respiration, we need to get glucose into our cells. The first step is to eat a carbohydrate-rich food, made of glucose. Let's say we eat a cookie. That cookie travels through our digestive system, where it is broken down and absorbed into the blood. The glucose then travels to our cells, where it is let inside. Once inside, the cells use various enzymes, or small proteins that speed up chemical reactions, to change glucose into different molecules. The goal of this process is to release the energy stored in the bonds of atoms that make up glucose. Let's examine each of the steps in cellular respiration next. Steps of Cellular Respiration There are Continue reading >>
Nearly 400 million people worldwide are living with diabetes, and that number is expected to jump to almost 600 million by 2035, according to the International Diabetes Federation. For many people, diabetes can be controlled with diet, exercise and, often, insulin or other drugs. However, complications from diabetes can be serious and include kidney failure, nerve damage, vision loss, heart disease and a host of other health issues. In this section: What is diabetes? How is diabetes treated? How are we using stem cells to understand diabetes? What is the potential for stem cells to treat diabetes? At its most basic, diabetes is a condition in which the body cannot regulate or properly use sugar (called glucose) in the blood. The pancreas, which helps the small intestine digest food, has hundreds of thousands of cell clusters called islets of Langerhans where beta cells live. Beta cells produce insulin, which is released into the bloodstream when blood sugar levels reach a certain threshold. The insulin signals other cells in the body to take up sugar, the primary energy source for all the body’s cells. Type 1, also known as juvenile diabetes. In type 1 diabetes, the body’s immune system attacks the beta cells in the pancreas. When the beta cells are damaged, they don’t produce insulin, or at least not enough insulin. Other cells never get the signal to take up sugar, so they don’t get the energy they need to function properly, and high sugar levels in the blood end up causing damage to the kidneys, eyes, nervous system and other organs. Type 2 diabetes, also called adult-onset diabetes. In type 2 diabetes, cells in the body become resistant to insulin. They don’t respond to the signals insulin sends out, so they don’t take up sugar from the blood. The beta c Continue reading >>
The Ketogenic Diet And Insulin Resistance
We recently touched on how you can use the ketogenic diet to control symptoms of diabetes such as elevated glucose and triglycerides. In this article, we examine research showing the impact that the ketogenic diet has on levels of the hormone insulin, a key regulator of blood sugar in the body. What is Insulin’s Role in the Body? Before we look at the research, we need to know our main players. Insulin is a protein-based hormone produced by beta-cells located in the pancreas. The pancreas, which is located under the stomach, also produces enzymes that aid with digestion. Insulin’s primary purpose is to regulate the metabolism of fats and carbohydrates. The digestive system breaks down carbohydrates, such as sugars and starches, into a molecule called glucose. This compound can be used by cells to produce energy through a process called cellular respiration. Insulin allows cells in the body absorb glucose, ultimately lowering levels of glucose in the blood stream. After a meal is consumed, blood glucose levels increase and the pancreas responds by releasing insulin into the blood. Insulin assists fat, liver, and muscle cells absorb glucose from the blood, resulting in lower levels of blood glucose. Insulin stimulates liver and muscle tissues to store excess glucose as a molecule called glycogen and also reduces glucose production by the liver. When blood sugar is low, the hormone glucagon (produced by alpha-cells in the pancreas) stimulate cells to break down glycogen into glucose that is subsequently released into the blood stream. In healthy people who do not have type II diabetes, these functions allow levels of blood glucose and insulin to stay in a normal range. What Is Insulin Resistance and Why Is It a Problem? Unfortunately, for many Americans and other peopl Continue reading >>
A&p - Ch 24
organic molecule that stores and releases chemical energy for use in body cells Flashcards Matching Hangman Crossword Type In Quiz Test StudyStack Study Table Bug Match Hungry Bug Unscramble Chopped Targets Nutrition, Metabolism, and Body Temp Regulation Question Answer organic molecule that stores and releases chemical energy for use in body cells ATP how energy value of food is measured; amount of heat energy needed to raise body temp of 1kg of water 1degree C kilocalories chemical substances taken in via the diet that are used for energy and cell building nutrients carbohydrates, lipids, & proteins major nutrients vitamins, minerals, & water other nutrients chemicals that must be obtained from outside sources because they cannot be made fast enough to meet needs of body essential nutrients except for lactose & negligible amounts of glycogen in meats all carbs ingested are derived from plants monosaccharides & disaccharides come from fruits, sugar can, sugar beets, honey & milk polysaccharide, plentiful in most veges; not digested by humans but provides roughage cellulose insoluble fiber roughage increases bulk of stool & facilitates defecation insoluble fiber reduces blood cholesterol levels; pectin found in apples & citrus fruits soluble fiber glucose is principal __ __ blood sugar carbohydrate molecule ultimately used as fuel by body cells to produce ATP; monosaccharide glucose yield of fructose & galactose, during carbohydrate digestion, are converted to glucose by liver before entering general circulation RBCs & neurons rely __ __ on glucose for their energy needs almost entirely small amounts of __ __ are used to synthesize nucleic acids pentose sugars variety of sugars are attached to externally facing plasma membrane __ & __ proteins; lipids 100 grams of carbs Continue reading >>
Fructose – The Good, The Bad – And The Malabsorbed...
Fructose – the good, the bad – and the malabsorbed... Michelle Berriedale-Johnson explains. The Good... When the Glycaemic Index first hit public awareness in the 1990s, fructose was hailed as the great white hope of diabetics. The index measured the speed at which foods, mainly carbohydrates, were converted into glucose in the body and fructose came very low on the index as it ‘converted’ very slowly into glucose. Glucose provides energy that the human body and brain need to function. It is absorbed from the gut into the blood stream and thence into the liver where it is converted and stored as a substance called glycogen. Glycogen is released back into the blood stream to be converted into energy by whichever part of the body is in need of energy as, when and in the quantities that it is needed. This process is monitored and regulated by the hormone insulin. If the release is not properly controlled either too much glucose (sugar) ends up in the blood which becomes sticky. Gradually it will clog up the tiny veins in the eyes, kidneys and extremities and, in due course, larger veins leading to the main organs such as the heart. If too little glucose/glycogen gets into the blood the body does not have enough energy to function at all. Insulin ensures that the glucose from the food that we have eaten, is converted, stored and released in the right amounts, as needed, to fulfil our bodies’ and brains’ energy requirements. The problem for diabetics is that they either do not produce any insulin, or do not produce the right amount at the right time to ensure the correct release of energy-providing glucose (or glycogen) into the blood stream. So, if they eat a lot of sweet and/or high carbohydrate foods that convert very quickly into glucose, the glucose will flo Continue reading >>
Diabetes - What is it and How Can You Control it? Diabetes. It's an insidious disease. When many people think about the term diabetes, they think about sugar, and nothing else. While, essentially, diabetes refers to a deficiency in the way your body handles sugar, we need to think about food, in general, when discussing diabetes. For many people with the disorder or disease, their blood sugar remains well within a tolerable range, well below 200 mg/dl; but there are those who, for one reason or another, have difficultycontrolling their blood sugar, and that leads to problems. So, let's look at the real problems with diabetes and help define just what it is. Diabetes refers to the body's inability to handle sugar, mainly glucose, which is the simplest for of sugar available for the body to use. If you recall or had any biology in school, then you might remember Kreb's Cycle. Glucose, a simple six-carbon sugar, enters the cell and goes through a series of changes (Kreb's cycle) which ultimately releases energy, in the form of ATP (adenosine tri-phosphate). This is the "gas" for the cell to stay alive and function. Well, along comes diabetes, which, in its simplest terms, refers to a problem getting sugar (glucose) out of the blood and into the cell (through the cell membrane). In order to enter the cell, glucose (the sugar) must "attach" itself to a "receptor" on the cell wall, which allows it to be transported through the cell membrane. The "vehicle" used for the transport is called insulin. Insulin is a protein (hormone) which is manufactured and released by the pancreas, an endocrine organ which sits above and to the right of the gallbladder (under the liver). If your pancreas does not secrete any insulin (or not enough), then you have diabetes, and you blood sugar wil Continue reading >>
What Is Lymph?
I was working on a yard project the other day and I ended up cutting myself with a utility knife. It was more a puncture than a cut, pretty deep but not very big. Anyway, the weird thing is that it didn't bleed. Instead, this clear fluid oozed out. What was that clear fluid? Assuming that you are not a space alien of some sort, the clear fluid that you saw was lymph. Apparently, when you cut yourself you did not puncture any sort of blood vessel, so you had a rare opportunity to actually see your lymph! One of the amazing things about lymph is that we all have it but we generally know nothing about it. Your entire body is soaked in lymph and there is a whole lymph vessel system that is just as complex as your blood vessels! Every human has a heart, arteries, veins, blood vessels and ultimately capillaries. Blood carries many different things to the cells, including: Oxygen (blood also picks up carbon dioxide so it can be exhaled) Proteins Glucose White blood cells (to find and eliminate bacteria, viruses and other foreign materials) Capillaries flow past cells but do not actually connect to them. What happens is that the clear, watery blood plasma -- containing the oxygen, proteins, glucose and white blood cells -- "leaks" out through the capillary walls and flows around all the cells. The pores in the capillaries are too small to let red blood cells through, however -- that is why lymph is clear rather than red. All of the cells in your body are therefore bathed in lymph, and they receive their nutrients and oxygen from the lymph. Somehow, all of this lymph has to end up somewhere, so it is recirculated. The lymph capillaries and vessels pick up the lymph fluid and start pumping it away from the cells. Lymph vessels do not have an active pump like the heart. Instead, l Continue reading >>
The Science Behind Bonking
Chiang Kai-shek is said to have received news of his army's mutiny while still in his pajamas. Chances are you will be equally unprepared for the mutiny of your own body--in other words, for bonking. We're not talking about the mere cramping of a calf, or the everyday slowing caused by lactic acid build-up, or the deep muscle pain sometimes caused by downhill running. Marathoners used to call bonking "hitting the wall," but it's actually a bodily form of sedition. In some form or another, it becomes a collapse of the entire system: body and form, brains and soul. Consider the muscle-glycogen bonk, where the brain works fine but the legs up and quit. Then there's the blood-glucose bonk, where the legs work fine but the brain up and quits. Let's not forget the everything bonk, a sorry stewpot of dehydration, training errors, gastric problems, and nutrition gaffes. And then there's the little-purple-men bonk. "After about 20-K, I started to see little purple men running up and down the sides of these cliffs," says Mark Tarnopolsky, M.D., who wears hats as both a leading sports nutrition researcher and an endurance athlete. "I knew it was an hallucination, but I stopped in the middle of the race to look at them anyway," he says. "It was kind of crazy." If you have run a distance race, chances are you have already become an aficionado of the bonk. You remember how your form held until you hit mile 18 and your feet turned into scuba fins. How your motivation held until you faced that last hill and became preoccupied with the idea of lying down on the pavement. Or, if you bonked thoroughly enough, how you began to see beings that belong in Dr. Seuss. And you thought sports nutrition was dull. And now, the field is undergoing the scientific version of a food fight. The sanctity Continue reading >>