Term
| a carbohydrate consisting of a single sugar unit |
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Definition
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Term
| a carbohydrate made of two sugar units |
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Definition
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Term
| monosaccharides and disaccharides are known as ______ because of their small size |
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Definition
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Term
| single sugar units that consist of carbon, hydrogen, and oxygen atoms in ratio of 1:2:1. Glucose is the most abundant carbohydrate in the body and consists of 6 carbons, 12 hydrogens, and 6 oxygens. |
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Definition
| description of monosaccharides |
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Term
| The most abundant monosaccharides found in food are 6-carbon sugars called _____. These include glucose, fructose, and galactose. |
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Definition
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Term
| What two shapes, or structures do monosaccharides usually exist in? |
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Definition
| cyclic or ring structures |
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Term
| Note: Although fructose has a 5-sided ring structure, it is still classified as a hexose b/c it contains a total of 6 carbons. |
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Definition
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Term
| Note: glucose and galactose look identical. However, the hydroxyl groups on carbon 4 face in opposite directions. Minor structural differences affect digestion, absorption, and physiological functions. |
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Definition
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Term
| sugar also known as "blood sugar". most abundant monosaccharide in the body. The primary function is to provide a source of energy to cells. The nervous system (the brain)and read blood cells generally use this sugar as their primary energy source. It can be converted in to amino acids and fat for long-term energy storage. |
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Definition
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Term
| The body stores small amounts of glucose as a compound called ______. |
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Definition
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Term
| sugar also known as "levulose". Naturally occuring monosaccharide found in honey, fruits, and vegetables. Of all the monosaccharides, this one is the sweetest. A 6-carbon monosaccharide. |
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Definition
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Term
| One of the monosaccharides that make up the disaccharide lactose. This sugar is the major carbohydrate in milk. Found as the carbohydrate component of glycolipids and glycoproteins, which are part of the cell membrane. This monosaccharide is converted to glucose and used as energy. |
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Definition
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Term
| lipids that contain carbohydrates |
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Definition
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Term
| proteins with carbohydrates attached |
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Definition
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Term
| proteins with carbohydrates attached |
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Definition
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Term
| proteins with carbohydrates attached |
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Definition
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Term
| Disaccharides consist of two monosaccharides bonded together. Name the 3 most common disaccharides. |
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Definition
| lactose, sucrose, maltose |
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Term
| What characteristic do the three disaccharides chare? |
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Definition
| at least one of the monosaccharides in the pair is glucose. |
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Term
| A condensation reaction chemically joins monosaccharides together by a ______ _______. |
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Definition
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Term
| What do alpha and beta designations indicate in glycosidic bonds? |
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Definition
| alpha & beta indicate whether the glycosidic bond is facing up or down. (alpha = face down) (beta = face up) |
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Term
| NOTE: the type of glycosidic bond (alpha or beta) determine whether a carbohydrate is digestible or indigestible. |
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Definition
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Term
| Glucose and fructose are two monosaccharides that make up the disaccharide _______. This disaccharide is found in plants, & is abundant in sugar cane and sugar beets. |
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Definition
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Term
| Two glucose monosaccharides make up the disaccharide ______. This disaccharide is also formed during starch digestion. |
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Definition
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Term
| A major disaccharide in the diet and is the most abundant carbohydrate in milk. Consists of glucose and galactose and is produced in the mammary glands. |
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Definition
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Term
carbohydrate made up of relatively few (3-10) monosaccharides. Known as a
complex carbohydrate. Present in a variety of foods, including dried beans, soybeans, peas, and lentils. Components of cell membranes, allows cells to recognize and interact with one another. Made in the breast where they are incorporated into human milk. |
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Definition
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Term
| a complex carbohydate made of many (10 or more) monosaccharides. |
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Definition
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Term
| what are the two most common oligosaccharides? [B/c humans lack the enzymes needed to digest these two, they pass undigested into the large intestine, where bacteria ferment them.] |
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Definition
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Term
| What are the three components that make up polysaccharides? |
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Definition
| starch, glycogen, and dietary fiber |
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Term
| NOTE: Plants store glucose as starch. Animals store glucose as glycogen. |
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Definition
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Term
| polysaccharide that has a structural role providing rigidity and strength to cell walls in plants. |
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Definition
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Term
| State the two forms of starch, both of which consist entirely of glucose molecules. |
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Definition
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Term
| linear, straight chained glucose molecule that is held together by alpha-1,4 glycosidic bonds |
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Definition
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Term
| glucose molecules that are bonded together in highly branched arrangments. linear portion of this molecule contains alpha-1,4 glycosidic bond, alpha-1,6 glycosidic bonds occur at branched points. [much more abundanct than amylose] |
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Definition
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Term
| The body stores small amount of glucose in the form of _____, which is found in the liver and skeletal muscles. This polysaccharide is a highly branched arrangement of glucose molecules, consisting of both alpha-1,4 and alpha-1,6 glycosidic bonds. This polysaccharide can be quickly broken down to allow glucose to be rapidly released when needed. |
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Definition
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Term
| NOTE: because most cells use glucose for energy, the body turns to glycogen during periods of limited glucose availability, such as fasting and strenuous exercise. |
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Definition
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Term
| a diverse group of plant polysaccharides that are not digested or absorbed in the humal small intestine. Indegestible b/c they contain beta-glycosidic bonds, which are resistant to digestive enzymes. Diets that contain this polysaccharide may be beneficial in preventing and treating obesity, cardiovascular disease, and type 2 diabetes. Found in a variety of plant foods such as whole grains, legumes, vegetables, and fruits. Classified by chemical composition, solubility, and other physical properties, such as water-holding capacity, viscosity, susceptibility to fermentation, and binding capacity. |
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Definition
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Term
| NOTE: soluble dietary fiber is recommended to help lower blood cholesterol levels and risk of cardiovascular disease. Insoluble fiber is recommended to alleviate constipation. |
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Definition
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Term
| NOTE: Some fibers have high water-holding capacities. These fibers form gel-like solutions in water and are viscous. Consuming these types of foods can increase stool weight and fecal volume, helping to prevent and alleviate constipation. |
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Definition
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Term
| Found in whole grains; resists bacterial breakdown and remains largely intact in the gastrointestinal tract. |
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Definition
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Term
| a mixed high fiber diet provides the best protection from constipation. Chronic constipation may lead to a more serious condition called _____. |
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Definition
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Term
| inflammation of diverticula (pouches) in the lining of the large intestine. |
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Definition
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Term
| NOTE: the ultimate goal of carbohydrate digestion is the breakdown of large, complex molecules into small, absorbable units - monosaccharides. This process begins in the mouth and requires a series of enzymes produced in various organs, including salivary glands, pancreas, and small intestine. |
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Definition
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Term
| enzyme released from the salivary glands, that digests starch by hydrolyzing alpha-1,4 glycosidic bonds. Hydrolyzes the alpha-1,4 glycosidic bonds in both amylose and amylopectin |
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Definition
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Term
| a partial breakdown product formed during starch digestion consisting of varying numbers of glucose units |
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Definition
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Term
| enzyme released from the pancreas that digests starch by hydrolyzing alpha-1,4 glycosidic bonds |
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Definition
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Term
| enzyme that hydrolyzes maltose into two glucose molecules. Produces in and located on the absorptive surface of the brush border cells, hydrolyzes maltose into glucose molecules |
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Definition
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Term
| intestinal enzyme that hydrolyzes sucrose into glucose and fructose. |
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Definition
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Term
| intestinal enzyme that hydrolyzes lactose into glucose and galactose |
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Definition
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Term
| NOTE: active transport of monosaccharides requires sodium and is therefore referred to as being "sodium dependent." Glucose and galactose are absorbed into the enterocytes by carrier-dependent, energy-requiring active transport. Fructose is absorbed by facilitated diffusion. Once absorbed, monosaccharides are circulated to the liver via tha hepatic portal vein. |
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Definition
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Term
| the impact of different foods on the magnitude and duration of the rise in blood glucose after a meal is called ______. |
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Definition
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Term
| a rating system known as the ______ ______ is used to classify foods according to their relative glycemic response. |
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Definition
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Term
| measure that assesses the effect of a food on blood glucose that takes into account both the glycemic index of a food as well as its carbohydrate content |
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Definition
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Term
| NOTE: unlike amylose, the digestion of amylopectin requires the enzyme alpha-dextrinase to hydrolyze alpha-1,6 glycosidic bonds |
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Definition
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Term
| two pancreatic hormones that work vigilantly to maintain blood glucose levels within an acceptable range at all times |
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Definition
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Term
| hormone secreted by the pancreatic beta-cells in response to increased blood glucose |
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Definition
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Term
| hormone secreted by the pancreatic alpha-cells in response to decreased blood glucose |
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Definition
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Term
| NOTE: the endocrine cells, known as the Islets of Langerhans, consists of beta cells that produce the hormone insulin and alpha cells that produce the hormone glucagon |
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Definition
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Term
| abnormally high level of glucose in the blood |
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Definition
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Term
| NOTE: the hormone insulin promotes the storage of excess glucose in the form of glycogen and body fat. Proteins called glucose transporters facilitate the movement of glucose molecules across the cell membrane. Binding of insulin to its receptor causes glucose transporters to relocate from the cytoplasm to the cell membrane. |
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Definition
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Term
| before excess energy from glucose can be stored, it must first be converted into glycogen or fat. Insulin controls the synthesis of glycogen, a process called ___________, which occurs mainly in the liver and skeletal muscles. |
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Definition
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Term
| NOTE: once glucose is transformed into a fatty acid, the fatty acid cannot be converted back into glucose |
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Definition
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Term
| abnormally low level of glucose in the blood |
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Definition
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Term
| Glucagon stimulates the breakdown of glycogen in the liver and release of glucose into the blood. The metabolic process, called ________, literally means the breakdown of glycogen. |
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Definition
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Term
| Muscle tissue is not responsive to the hormone glucagon; therefore it is glucagon insensitive. Muscle glycogenolysis occurs in response to the hormone ______, which is produced in the adrenal glands. |
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Definition
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Term
| Hormones can increase blood glucose when cells have an immediate need for energy. These hormones include epinephrine and _____, produced in the adrenal glands. |
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Definition
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Term
| NOTE: Epinephrine and cortisol stimulate liver and muscle glycogenolysis in response to danger or stress. Called the fight-or-flight response, ensures glucose availability, especially under extreme circumstances. |
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Definition
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Term
| synthesis of glucose from noncarbohydrate sources |
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Definition
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Term
| to minimize muscle loss assciated with gluconeogenesis, the body also uses an alternative energy source (instead of glucose) called _____. They are formed from fatty acids when there is a relative absence of glucose. |
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Definition
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Term
| metabolic pathway that leads to the production of ketones. Occurs in the liver and is stimulated by the hormone glucagon. |
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Definition
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Term
| a condition called _______ occurs when ketone production exceeds the rate of ketone use, resulting in the accumilation of ketones in the blood. This happens when energy intake is very low or when the diet provides insufficient amounts of carbohydrates |
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Definition
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Term
| NOTE: fiber may be important in preventing and treating diseases such as diabetes and heart disease. |
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Definition
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Term
| NOTE: dietary fiber has been shown to imporove blood glucose regulation, lower blood cholesterol, promote satiety, and contribute to healthy bowel function. |
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Definition
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Term
| NOTE: carbohydrates are needed to provide energy to cells. Tissues, such as the brain, typically rely on glucose for energy. |
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Definition
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Term
| NOTE: Dietary Reference Intakes are based mainly on ensuring that the brain has adequate glucose for its energy needs. The Recommended Dietary Allowance for carbohydrate is 130g per day for adults. Adequate Intake values for dietary fiber range from 21 to 38g per day for adults. |
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Definition
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Term
| NOTE: the current recommendation for adults is to consume an equivalent of 5 to 10 ounces of grain-based foods daily, half of which should be whole grain. It is also recommended that adults consume approximately 1.5 to 2.5 cups of fruit and 2 to 4 cups of vegetables daily. The Dietary Guidelines recommend that adults consume 14g of dietary fiber per 1,000 kcal. |
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Definition
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Term
| NOTE: Nutritionally, white bread, white rice, and white pasta are no match for their whole-grain counterparts. This is because the nutritional value of whole grain is greatest when all three layers of the wheat kernal - bran, germ, and endosperm - are intact. Milling removes the bran and germ layers, resulting in finely ground, refined flour. |
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Definition
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Term
| NOTE: foods made with whole-wheat flour are more nutritious than foods made with refined wheat flour, because the three layers of of the wheat kernal - bran, germ, and endosperm - are intact. Each layer contributes important nutrients needed for good health. Germ contains vitamins and minerals. Endosperm is mostly starch. Bran contains most of the fiber. |
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Definition
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Term
| Name the correct carbohydrate sequence of a monosaccharide followed by disaccharide followed by polysaccharide. |
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Definition
| glucose, maltose, amylose |
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Term
| A monosaccharide that has 6 carbon atoms also has ____ hydrogen atoms and _____ oxygen atoms. |
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Definition
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Term
| What carbohydrate is found in milk? |
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Definition
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Term
| Plants store glucose in the form of _____ whereas animals store glucose in the form of _____. |
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Definition
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Term
| What carbohydrate consists of a highly branched arrangement of glucose molecules? |
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Definition
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Term
| One difference between dietary fiber and amylose is that: |
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Definition
| amylose has alpha-glycosidic bonds, whereas dietary fiber has beta-glycosidic bonds |
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Term
| dextrins are formed furing the digestion of _____. |
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Definition
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Term
| NOTE: foods with high glycemic index cause a rapid and large surge in blood glucose levels. |
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Definition
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Term
| The hormone released from the pancreas that helps decrease blood glucose is called ___. |
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Definition
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Term
| What is an example of a good source of dietary fiber? |
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Definition
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Term
| fats and oils that are insoluble in water and more soluble in organic solvents such as fingernail polish remover and paint thinners. Hydrophobic and are made mostly of carbon, hydrogen, and oxygen atoms. Some contain phosphorus and nitrogen atoms. When liquid at room temperature they are considered oils. When solid at room temperature they are considered fats. |
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Definition
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Term
| NOTE: major lipid classes include the fatty acids, triglycerides, phospholipids, sterols, and fat-soluble vitamins. |
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Definition
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Term
| Known as the most abundant lipids and are made entirely of carbon, hydrogen, and oxygen atoms. Consists of a chain of carbon atoms, which form the backbone. One end of the backbone contains a carboxylic acid group (-COOH), known as the alpha end. The other end of the backbone contains a methyl group (-CH), known as omega end. |
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Definition
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Term
| NOTE: the chain length of a fatty acid affects its chemical properties and physiological functions. Because long-chain fatty acids tend to be more stable than short-chain fatty acids, they have higher melting and boiling points than short-chain fatty acids. If everything else is equal, long-chain fatty acids tend to be solid (fat) at room temp, & short-chain fatty acids tend to be liquid (oil) at room temp. Chain length also affects solubility in water, with short-chain fatty acids being more water soluble than long-chain fatty acids. |
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Definition
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Term
| a fatty acid that contains a single carbon-carbon bond |
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Definition
| saturated fatty acid (SFA) |
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Term
| a fatty acid that contains one or more double bonds |
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Definition
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Term
| fatty acids with one double bond |
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Definition
| monounsaturated fatty acids (MUFAs) |
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Term
| a fatty acid that contains more than one carbon-carbon double bond in its backbone |
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Definition
| polyunsaturated fatty acid (PUFAs) |
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Term
| NOTE: Like chain length, the number of double bonds influences the physical nature of the fatty acid. SFAs have straight, unbending structures that stack neatly together. Unsaturated fats can bend and therefore are more disorganized. |
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Definition
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Term
| NOTE: monounsaturated fatty acids have chemical characteristics that lie between SFAs and PUFAs, being thick liquids or soft solids at room temperature |
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Definition
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Term
| NOTE: Unsaturated fatty acids can differ by whether they have cis or trans carbon-carbon double bonds. Cis bonds cause the fatty acid to bend, whereas trans bonds do not. A cis fatty acid have hydrogen on the same side of the fatty acid backbone. A trans fatty acid have hydrogens on opposite sides of the fatty acid backbone. Fatty acids containing atleast one trans double bond are called trans fatty acids, and have fewer bends in their backbones than their cis counterparts. Trans fatty acids are more likely to be solid (fats) at room temperature |
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Definition
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Term
| NOTE: the alpha nomenclature system is based on the positions and types of double bonds relative to the carboxylic acid end of the fatty acid. Ex: cis9,cis12-18:2 = 18 carbons, 2 double bonds (cis) located at 9th & 12th carbon |
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Definition
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Term
| NOTE: omega nomenclature tells the number of carbons and double bonds. In omega nomenclature system fatty acids are categorized into groups based on where the first double bond is located relative to the methyl end of the molecule. [omega nomenclature does not identify whether the double bonds are in the cis or trans configuration] Ex: 18:2 |
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Definition
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Term
| NOTE: palmitic acid (16:0) is found in palm oil, and arachidonic acid (cis5, cis8, cis11, cis14-20:4) from arachis, found in peanuts |
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Definition
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Term
| What are the two essential fatty acids?> |
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Definition
| linoleic and linolenic acid |
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Term
| essential fatty acid that has 18 carbons, 2 cis double bonds, and is an omega-6 fatty acid. |
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Definition
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Term
| essential fatty acid that has 18 carbons, 3 cis double bonds, and is an omega-3 fatty acid |
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Definition
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Term
| a long-chain, polyunsaturated omega-6 acid produced from linoleic acid |
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Definition
|
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Term
| a long-chain, polyunsaturated omega-3 fatty acid produced form linolenic acid |
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Definition
| docosahexanoic acid (DHA) |
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Term
| The essential fatty acids can also be converted to other important compounds that are not themselves; A group of compounds made from arachidonic acid and EPA. Have profound, hormone-like effects, assisting and regulating the immune and cardiovascular systems and acting as chemical messengers that direct a variety of additional functions. |
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Definition
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Term
| NOTE: Linoleic acid (an omega-6 fatty acid) is metabolized to omega-6 eicosanoids; Linolenic acis (an omega-3 fatty acid) is metabolized to omega-3 eicosanoids |
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Definition
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Term
| NOTE: Adequate Intake levels for linoleic acids are 17 to 12 g/day for adult males and females. For linoleic acid, the Adequate Intake levels are 1.6 and 1.1 g/day for adult males and females. The AMDR for linoleic and linolenic acids are 5 to 10 and 0.6 to 1.2% of calories. |
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Definition
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Term
| NOTE: If humans do not consume enough of the essential fatty acids, their skin can become irritated and flaky, gastrointestinal problems can occur, and immune function can become impaired. As a result, infections are common and wound healing may be restricted. |
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Definition
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Term
| NOTE!!!!!: most saturated and unsaturated fatty acids are not essential in the diet, they serve a variety of functions, which include serving as sources of energy, insulation, and protection. |
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Definition
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Term
| NOTE: Animal foods contribute the majority of dietary saturated fatty acids. Plant-derived foods supply the majority of polyunsaturated fatty acids. Monounsaturated fatty acids come from both plant and animal foods. Many oily fish have high levels of polyunsaturated fatty acids. |
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Definition
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Term
| NOTE: Scientists have long known that SFA intake is positively related to risk for cardiovascular disease |
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Definition
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Term
| Trans fatty acids are found naturally in some foods - dairy and beef products. Most dietary trans fatty acids are produced commercially via a process called ____ _____, which chemically converts oily lipids into solid fats. |
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Definition
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Term
| NOTE: many public health agencies suggest that we limit our intake of trans fatty acids. This is b/c studies show that some of them increase the risk for cardiovascular disease. (recommended intake is <1% of calories from trans fatty acids) |
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Definition
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Term
| NOTE: Monoglycerides, triglycerides, and diglycerides play many roles, including serving as sources of energy, insulation, and protection. |
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Definition
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Term
| a glycerol molecule chemically bonded to three fatty acids via ester bonds. These fatty acids can be saturated, monounsaturated, polyunsaturated, or a mixture of fatty acids classes. Extremely hydrophobic. Provide essential fatty acids needed for the body to function. Also supply fatty acids used for energy production and storage. Also important for insulation and protection. |
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Definition
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Term
| Triglycerides provide an important source of energy. For this to happen, they must first be broken down into glycerol and fatty acids. This process, called lipolysis, is catalyzed by the enzyme _____-_____ _______, whose activity increases when secretion of the pancreatic hormone insulin is low. |
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Definition
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Term
| NOTE: Lipolysis is stimulated by exercise and in physiological stress. Fatty acids represent the body's richest source of energy. |
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Definition
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Term
| Fatty acids not required for energy or other functions in the body are stored as triglycerides in adipose tissue and skeletal muscle. Adipose tissue consists of specialized cells called ______, which can accumulate large amounts of lipids. |
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Definition
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Term
A.) Adipose tissue found directly under the skin.
B.) Adipose tissue surrounding the vital organs. |
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Definition
a - subcutaneous adipose tissue
b - visceral adipose tissue |
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Term
| NOTE: the pancreatic hormone, insulin, stimulates the storage of triglycerides during times of energy excess |
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Definition
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Term
| Fatty acids are incorporated into triglycerides. The synthesis of fatty acids and triglycerides is called ______. |
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Definition
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Term
| NOTE: triglycerides stored in adipose tissue also insulate the body and protect internal organs from injury. Adipose tissue also serves important roles in temperature regulation and protection. |
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Definition
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Term
| A lipid composed of a glycerol bonded to two fatty acids and a polar head group. There is no dietary requirement for this lipid class. Similar to triglycerides in that they contain a glycerol molecule boneded to fatty acids, but instead of having 3 it only has 2. Replacing the 3rd fatty acid is a polar head group. These lipids are amphipathic (polar and nonpolar ends). Major component of cell membranes and play roles in the digestion, absorption, and transport of lipids. Make up the major structural component of cell membranes. |
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Definition
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Term
| NOTE: there are many different types of polar head groups, but the most common are choline, ethanolamine, inositol, and serine. |
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Definition
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Term
| NOTE: cell membranes consist of two layers (a bilayer) of phospholipids with the hydrophilic polar head group pointing to the extracellular and intracellular spaces. |
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Definition
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Term
| NOTE: If the cell membrane were completely hydrophilic, it would dissolve and not create a barrier. If the cell membrane were complete hydrophobic, there would be chance of communication between water extracellular and intracellular compartments. The incorporation of amphipathic phospholipids allows cell membranes to effectively carry out their functions. |
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Definition
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Term
| NOTE: Phospholipids have active enzymes important for energy metabolism, blood clotting, and cell turnover. Phospholipids act as carriers of hydrophobic substances in the body. |
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Definition
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Term
| The incorporation of phospholipids on the outer surface of a class of compounds is called ______. They transport lipids in the blood. |
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Definition
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Term
| a phospholipid with a choline polar head group that is often added as a stabilizer to foods such as mayonnaise and ice cream is known as ______. You can check whether or not foods contain this molecule by looking for the word "lecithin" on the food label. |
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Definition
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|
Term
| a phospholipid with a serine polar head group |
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Definition
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Term
| a type of lipid with a distinctive multiring structure; a common example is cholesterol. |
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Definition
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Term
| a sterol can be attached to a fatty acid via an ester bond forming a ___ ___. |
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Definition
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Term
| a weakly polar compound; known as the most abundant sterol; Most of these molecules bond to fatty acids. A sterol found in animal foods and made in the body; required for bile acid and steroid hormone synthesis. Play a critical role in digestion and absorption of lipids. Also a component of the cell membrane where it helps maintain fluidity. |
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Definition
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|
Term
| a sterol ester made of a cholesterol molecule bonded to a fatty acid via an ester linkage. More hydrophobic than free cholesterol. A component of cell membrane where it helps maintain fluidity. Also serve as a crucial carrier molecule for fatty acids in the blood. |
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Definition
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|
Term
| amphipathic substances made from cholesterol in the liver; a component of bile important for lipid digestion and absorption. Consist of bacis, multiring structure of cholesterol attached to a very hydrophilic subunit |
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Definition
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Term
| a hormone made from cholesterol. Cholesterol is needed for the synthesis of this molecule. This molecule is important for reproduction, energy metabolism, calcium homeostasis, and electrolyte balance. |
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Definition
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Term
| NOTE: Cholesterol is made from glucose and fatty acids in almost every tissue in the body, especially the liver. Eating a low-calorie diet can decrease cholesterol synthesis in some people. Cholesterol synthesis can be lowered by medical means by taking statin drugs such as Lipitor and Zocor that decrease blood cholesterol by inhibiting one of the enzymes needed for its synthesis in the liver. |
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Definition
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|
Term
| NOTE: Cholesterol is found only in animal-derived foods, such as shellfish, meat, butter, eggs, and liver. Cholesterol content of liver is very high, b/c it is the body's major site of cholesterol synthesis and storage. B/c cholesterol is a nonessential nutrient, vegetarians are not at risk of cholesterol deficiency. |
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Definition
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|
Term
| plants also contain sterol-like compounds called ______, which are chemically similar to cholesterol. These compounds can be hydrogenated in foods to produce compounds called stanols. An interesting group of these compounds can be found in butter substitutes, yogurt drinks, salad dressings, and even dietary supplements. May help decrease blood cholesterol concentration, lowering the risk for cardiovascular disease. |
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Definition
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|
Term
| NOTE: Once lipids have been ingested, they must be digested, absorbed, and circulated away from the gastrointestinal tract. Lipid digestion occurs in the mouth, stomach, and small intestine, involving several enzymes and other secretions such as bile. The basic goal of triglyceride digestion is the seperation of most of the fatty acids from the glycerol molecule. The body has a series of enzymes calles LIPASE that accomplish this task. |
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Definition
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Term
| Digestion of triglycerides begins in the mouth. As chewing breaks apart food, ___ ___, (an enzyme produced by the salivary glands) begins to hydrolyze fatty acids from glycerol molecules. As food is swollowed this component accompanies the bolus into the stomach, where it continues to cleave additional fatty acids. |
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Definition
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Term
| When food enters the stomach, it stimulates the release of the hormone gastrin from specialized cells lining the gastric pits. Gastrin circulates in the blood and stimulates the release of the enzyme ____ ____, which is also produced in the stomach cells. It is a component of the "gastric juices" and picks up where lingual lipase left off, by continuing to cleave fatty acids from glycerol molecules. |
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Definition
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|
Term
| the process of breaking larger lipid globules into smaller droplets is called ______. |
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Definition
|
|
Term
| results in the production of smaller stable lipid particles is called _____. |
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Definition
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Term
| NOTE: the presence of lipids in the small intestine stimulates enterocytes to secrete the hormone cholecystokinin, which in turn signals the gallbladder to contract and release bile into the duodenum. |
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Definition
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Term
| NOTE: Bile is a mixture of bile acids, free cholesterol, and phospholipids made by the liver and stored in the gallbladder until needed. Bile acids and phospholipids are amphipathic. The hydrophobic portions of these molecules associate with the lipid globules, whereas the hydrophilic portions associate with the surrounding water. These opposing forces pull the lipid globules apart into smaller droplets. Bile acids and phospholipids then stay with the newly formed droplets, preventing them from reforming larger globules. |
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Definition
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Term
| a lipid composed of a glycerol bonded to a polar head group and a fatty acid; final product of phospholipid digestion |
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Definition
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Term
| Free cholesterol does not need to be digested before absorption. Cholesterol esters must be broken down to their constituents: cholesterol & fatty acids. This is accomplished by another pancreatic enzyme known as ____. |
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Definition
| bile salt-dependent cholesteryl ester hydrolase |
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Term
| NOTE: Lipid absorption is accmplished in two ways, depending on how water-soluble (hydrophilic) the lipid is. Short and medium chain fatty acids can be transported into the enterocyte without further assistance. |
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Definition
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Term
| NOTE: more hydrophobic compounds such as long-chain fatty acids, monoglycerides, lysophospholipids, and cholesterol must first be repackaged into a second form of micelle within the intestinal lumen. The formation of these micelles require the help of bile. Once micelle comes in contact w/ brush border surface of the intestine, the contents can be released adn transported into the enterocyte. |
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Definition
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Term
| NOTE: short and medium chained fatty acids are somewhat hydrophilic and therefore can be circulated away from from the small intestine in the blood. They are first bound to the protein albumin. Fatty acid-albumin complexes flow in the blood from the small intestine to the liver, where they are either metabolized or packaged for delivery to other cells in the body. |
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Definition
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Term
| Long-chain fatty acids, monoglycerides, and lysophospholipids must firt be resynthesized back into trigylcerides and phospholipids in the enterocyte. These large lipids combine with cholesterol and cholesteryl esters and are then incorporated into particles called _____, which are released into the lymph for initial circulation. The largest and least dense members of a class of sustances called lipoproteins. |
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Definition
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Term
| NOTE: b/c lipid is less dense than protein, the densities of the lipoproteins depend on their relative amounts of lipids and proteins. Lipoproteins with relatively more lipid than protein have lower densities than those with more protein and less lipid. Most lipoproteins are named according to their densities. The basic function of lipoproteins is to transport lipids in the hydrophilic environments of the body. |
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Definition
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Term
| Chylomicrons deliver fatty acids to the body via an enzyme called ___ ____, which is produced in many tissues, especially adipose and muscle. Enzyme that hydrolyzes the ester bond between a fatty acid and glycerol in a triglyceride molecule. After it is produced, this enzyme is relocated out of these cells and into the lumen of the neighboring capillary blood vessels. |
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Definition
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Term
| The lipoprotein particle that remains after a chylomicron has lost most of its fatty acids. The remnants are taken up by the liver, where they are broken down and their contents reused or recycled. |
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Definition
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Term
| NOTE: the liver synthesizes and metabolizes lipids as needed. The liver serves as the central command center for lipid metabolism. The liver also makes lipoproteins required for the delivery of newly synthesized lipids. |
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Definition
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Term
| major function involves delivery of dietary and other fatty acids; loss of fatty acids |
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Definition
VLDL - very low density lipoprotein
IDL - intermediate-density lipoprotein |
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Term
| lipoprotein with major function involving delivery of cholesterol |
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Definition
| LDL - low-density lipoprotein |
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Term
| lipoprotein with major function involving picking up excess cholesterol from cells for delivery back to the liver |
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Definition
| HDL - high-density lipoprotein |
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Term
| lipoprotein with major function involving delivery of dietary fatty acids |
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Definition
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