Nutrition Ch. 4 Carbohydrates

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What are Carbohydrates?
Coumpunds composed of single or multiple sugars
What are Complex Carbohydrates? What is the other name for them?
long chains of sugar units arranged to form starch or fiber.
Also called polysacharides
What are Simple Carbohydrates?
sugars, including both single sugar units and linked pairs of sugar units.
Describe the basic molecule of a simple carbohydrate?
Simple Carbohydrate = 6 carbon atoms together with oxygen and hydrogen atoms.
What is Photosynthesis?
The process by which green plants make carbohydrates from carbon dioxide and water using the green pigment cholorophyll to capture the suns energy.
Define Chlorophyll
the green pigment of plants that captures energy from sunlight for use in photosynthesis.
What are Sugars?
What does the term Sugar most ofen refer to?
Sugars = simple carbohydrates; molecules of either single sugar units or pairs of those sugar units bonded together.
Sugar most often refers to sucrose
Define Glucose
Glucose = single sugar used in both plant and animal tissues for energy; sometimes known as blood sugar or dextrose.
what are Monosaccharides?
Monosaccharides = Single sugar units
pairs of single sugars linked together
Where do most carbohydrates come from in the diet?
What is the one exception?
Carbohydrates are almost exclusively from plants.
One exception is milk
What importance is light from the sun to glucose?
Light energy drives the photosynthesis reaction by becoming the chemical energy of the bonds that hold six atoms of carbon together in the sugar glucose.
How many sugars are important in nutrition and how are they classified?
6 sugars are important in nutrition
1) 3 Monosacccharides
2) 3 Disaccharieds
What are the Monosaccharides?
Define Galactose
Where is it found in food?
1 or 2 single sugars that are bound together to make up the sugar of milk.
Rarely found in nature - tied up in milk sugar until it's released during the digestive process.
What are the Disaccharides?
Define Lactose
Lactose - a type of mlk sugar - glucose is linked to galactose
Define Maltose
Where does it come from?
Maltose = malt sugar
Maltose appears wherever starch is being broken down (digestive process) and in germinating seeds.
What is Sucrose?
What forms Sucrose?
Table Sugar
Sucrose = Fructose and Glucose bonded together
Where does Sucrose primarily come from in the food supply?
Beet and Cane Sugar
Why does Sucrose taste sweet?
It tastes sweet b/c it contains the sweetest of the monosaccharides - fructose.
What is the most important monosaccharide in the human body?
How are Monosaccharides and Disaccharides processed by the body (differently)
Monosaccharides are absorbed directly into the bloodstream
Disaccharides much be digested first
What do most monosaccharides and disaccharides become in the body?
What are Polysaccharides?
also known as Complex Carbohydrates
Compounds composed of long strands of glucose units linked together
What is starch?
A plant polysaccharide composed of glucose
Plants storage form of glucose
How is starch digested by the body?
After cooking = highly digestible
Raw - resists most digestion
What are Granules?
What are they composed of?
In plants what do starch granules look like?
Small grains.
Starch granules are packages of starch molecules.
Various plant species make starch granules of varying shapes.
What is Glycogen?
Glycogen - Highly branched polysaccharide that is made and stored by liver and muscle tissues of human beings and animals as a storage form of glucose.
Is Glycogen a significant food source?
No - it is one of the significant food sources and is not counted as one of the comlplex carbohydrates in foods.
How is Glucose stored in the human/animal body?
Glucose is stored in long chains of starch in human and animal bodies.
What is the storage form of glucose in animals and human beings?
What is fiber?
what is fiber made of (molecularly)
Fiber = indigestible parts of plant foods
Fiber = largely non-starch polysaccharides that are not digestd by human digestive enzymes.
Name 6 types of Fiber
nonpolysaccharide lignin
What are Soluble Fibers?
Soluble Fibers = food components that readily dissolved in water and often impart gummy or gel like characteristics to foods
How are soluble fibers processed by the human body?
Soluble Fibers are indigestible by human enzymes but easily broken down by bacteria in the colon. (fermentation)
Where are Soluble Fibers found in the food supply?
What are their benefits?
Soluble Fibers are found in Oats, barley, legumes, citrus fruits.
They can help lower blood cholesterol.
What are insoluble fibers?
How are they processed by the body?
Insoluble Fibers -
1) the tough, fibrous structures of fruits, vegetables, and grains.
2) Indigestible - do not dissolve in water
Where are Insoluble Fibers found in the food supply?
What are their benifits to us?
1) Celery, outer layer of grains, hulls of seeds, skins of corn kernels
2) Aids by easing elimination
When plants combine Co2, the suns energy, and water what do they produce and how to they store it?
Plants produce glucose then store it as the polysaccharide starch.
What happens (energywise) when humans/animals eat plants?
1) humans eat plants and retrieve glucose.
2) in the body the liver and muscles may store the glucose as the polysaccharide glycogen, but ultimately it becomes glucose again.
What happens when glucose breaks down?
It breaks down into the waste products Co2 and Water, which are excreted
Why is Glucose important?
Glucose from carbohydrate is an important fule for most body functions.
What are the preferred sources of glucose in the diet?
Starchy whole foods that supply complex carbohydrates, especially fiber rich ones are the preferred source of flucose in the diet.
What is the DRI reccomendation for carbohydrates in the form of total daily energy intake?
What are the 5 benefits of Fiber?
1. promtion of normal bood cholesterol concentrations
2. control of blood pressure
3. modulation of blood glucose concentrations
4. maintenance of health bowel functions
5. promotion of healthy weight
How are foods rich in viscous fiber a benefit to us?
They combine with cholesterol-containing compounds in bile (excretion).
What benefit does fiber have in the GI tract?
1. simulates the GI tract muscles so they resist bulging out into pouches known as diverticula
2. acctracts water which dilutes cancer causing agents and speeds their elimination (including nitrogent)
3. creats feeling of fullness
4. supply phytochemicals
4. economical and nutritious.
How much fiber does the ADA reccomend daily? (g)
20-35g daily
Chelating Agents
Chelating Agents = molecues that attract or bind with other molecules and are therefore useful in eithe rpreventing or promoting movement of substances from oplace to place.
What is the relationship b/w fibers and chelating agents?
Binders in some fibers act as chelating agents.
They link chemically with important nutrient minerals (iron, zink, calcium, others) and carry them out of the body.
What are the drawbacks to too much fiber?
1)Too much fiber will limit absorption of nutrients by speeding foods through the upper digestive tract.
2) Can carry too much water out of the body and cause dehydration
3) Feelings of fullness my lead to under eating thus malnourishment.
How do Starch and Disaccharides differ in their breakdown in the body?
Starch requires the most extensive breakdown before it can be absorbed.
Disaccharides only need to be split once
Where does digestion of Starch begin?
Describe the process.
1. Digestion of Starch begins in the mouth where it is broken down by saliva and split into maltose.
2. Digestion stops in the stomach but resumes in the large intestine.
3. The large intestine breaks it down into polysacharides and disaccharides that are absorbed high up in the small intestine.
What is resistant starch and what is an example of where it's found in the food supply?
Resistant Starch - The fraction of Starch that is digested slowly or not at all by human enzymes.
1. digests more slowly and releases it's glucose later in the process.
Example - beans
Where is resistant starch found in food and what are it's health benefits?
1. Resistant Starch = barley, shilled cooked potatoes and pasta, cooked dried beans and lentils, oatmeal, underripe bannannas.
2. May suppport a health colon.
1.Desribe the splitting of Sucrose, Lactose, Maltose, and small polysaccharides freed from food.
2.What happens once they are split? (4 Steps)
1. They undergoe one more split to yield free monosaccharides before they are absorbed.
1. split is accomplished by enzymes attached to the wall of the small intestine.
2. monosaccharides cross these cells and are washed away by blood to the liver.
3. liver converts fructose and galactose to glucose.
4. circulatory system transports glucose and other poducts to the cells.
Which of the bodies cells split glucose for energy?
All of them
How does the liver and muscle cells store circulating glucose?
As glycogen
What changes fibers most, digestive enzymes or bacterial inhabitants of the colon?
Most fibers are not changed by digestive enzymes,
They are digested (fermented) by bacteria in the colon.
What is Lactase?
The intestinal enzyme that splits the disaccharide lactose to monosaccharides during the digestion.
What is lactase relationship to an infant?
Infants produce abundant lactase so they can digest mothers milk.
What happens to glucose once it is broken down?
It is lost forever and becomes other substances that yeild energy to the body .
What is the glucose/body fat relationship?
Glucose can be converted into body fat but never the other way around to feed the brain adequately.
What happens if the body runs short of glucose?
The body must turn to protein to make energy, robbing blood, organs, or muscle proteins.
What is Protein Sparing Action?
Action of carbohydrate and fat in providing energy that allows protein to be used for purposes it alone can serve.
What are Ketone Bodies?
Acidic, fat-related compounds that can arise from the incomplete breakdown of fat when carbohydrate is not available.
An undesireable high concentration of ketone bodies, such as acetone, in the blood or urine.
What are 5 consequences of inadequate carbohydrate intake?
1. accumulation of ketone bodies that disturb the normal acid/base balance.
2. moodiness
3. kidney stones
4. vit/mineral deficiencies
5. elevated blood cholesterol
What is the DRI minimum carbohydrate level for adults? (g)
130g of carbohydrate a day.
What is the DRI minimum carbohydrate level for adults? (g)
130g of carbohydrate a day.
What symptoms does abnormally high glucose cause?
confusion/difficulty breathing
What symptoms does abnormally low glucose cause?
dizziness, weakness
What 2 safeguard mechanisms does the body use to keep glucose balanced?
1. Siphons off excess blood glucose into liver and into muscles for storage as glycogen and to the adipose tissue for storage as body fat.
2. Replenishes diminished blood glucose from liver glycogen stores.
What is Insulin and what does it do?
A hormone secreted by the pancreas in response to a high blood glucose concentration.
Assists cells in drawing flucose from the blood.
Describe the action of Insulin after a meal (4 steps)
1. Blood glucose rises and pancrease respond
2. Pancreas relase insulin which signal body tissues to take up surplus glucose
3. Muscle and adipose tissue respond by taking up some glucose to build the polysaccharide glycogen or convert it into fat.
4. Liver takes up excess glucose and makes glycogen too, but it needs no help from insulin to do so.
Describe the action of Insulin after a meal (4 steps)
1. Blood glucose rises and pancrease respond
2. Pancreas relase insulin which signal body tissues to take up surplus glucose
3. Muscle and adipose tissue respond by taking up some glucose to build the polysaccharide glycogen or convert it into fat.
4. Liver takes up excess glucose and makes glycogen too, but it needs no help from insulin to do so.
Where is most of the glycogen in the body stored?
The muscles store the most glycogen (2/3)
What is the brains relationship to glycogen?
The brain stores a tiny amount of glycogen for an our or two in case of deprivation.
What is the livers relationship to glycogen?
The liver stores glycogen and realeases glucose into the bloodstream for the brain and other tissues when the supply runs low.
What is the livers relationship to glycogen?
The liver stores glycogen and realeases glucose into the bloodstream for the brain and other tissues when the supply runs low.
What happens to the liver if the body runs out of carbohydrate from food?
The liver can be depleted of glycogen stores in less than one waking day.
How does the liver release glucose?
When blood glucose starts to fall too low, the hormone glucagon floods the bloodstream and triggers the breakdown of liver glycogen to free glucose.
Enzymes w/in liver cells resond to glucagon by attacking a multitude of glycogen ends simultanewously to relase a surge of glucose into blood.
How is glucose stored in the liver?
Glucose is stored in the liver as Glycogen.
T or F, Muscles store their own glycogen.
What is the action difference between insulin and glucagon?
Insulin promotes glycogen storage.
Glucagon acts to liverate glucose from liver glycogen.
A blood glucose concentration that is below normal.
What could hypoglycemia indicate?
Several diseases including Diabetes.
Sugar Alcohols
Sugarlike compounds in the chemical family alcohol derived from fruits or the sugar dextrose that are absorbed more slowly than other sugars.
They are metabolized differently, and do not elevate the risk of dental caries.
Dental Caries
Decay of the teeth.
T or F, Artificial sweeteners are sugar substitues that provide modest energy.
False - artificial sweeteners provide no energy.
T or F, Artificial sweeteners are sugar substitues that provide modest energy.
False - artificial sweeteners provide no energy.
What is postprandial hypoglycemia?
What is another name for it?
unusual drop in blood glucose that follows a meal and is accompanied by symptoms such as anxiety, rapid heartbeat and sweating.
Also called reactive hypoglycemia
What does the body do with excess glucose once the liver and muscle stores are full?
What are the results?
body tissues shift from burning fat for energy to burning glucose for energy.
The excess of fat is left to circulate in the bloodstream until it's picked up by by the fatty tissues and stored there.
Glycemic Index
Ranking of foods according to their potential for raising blood glucose relative to a standard such as glucose or white bread.
Glycemic Load (GL)
A mathematical expression of both the glycemic index and the carbohydrate content of a food, meal or diet
(glycemic index x carbohydrate)
How are Carbs stored as Fat? (3 steps)
1. Liver breaks down excess glucose into fats
2. fats are released into the blood, carried to adipose tissues
3. fat cells also take up some glucose directly and convert it to fat.
How much glycogen can the liver store?
About 2000 calories.
how much fat can the average size person store in fat cells?
Fat cells = 70,000 calories and are almost limitless in size.
When the body is presented with both glucose and fat from a mixed meal, what does it do?
The body will store fat and use glucose for immediate energy needs.
Which is higher on the GI scale, Ice Cream or Potatoes?
Potatoes rank higher - they are all glucose
Ice Cream is made of sucrose, and fructose is half of each sucrose molecule. Fructose is low on the GI scale.
Why is the GL important to diabetics?
The lower the GL the less insulin needed to maintain normal glucose concentraions.
What affects someones glycemic response?
body size, weight, blood volume, metabolic rate
T or F, the glycemic response to foods is fairly standard in normal healthy adults.
False, the glycemic response varies between individuals.
What are some food factors that have an influence on glycemic index results.
Plant variety
other foods eaten at the same time
A disease characterized by elevated blood glucose and inadequate or ineffective insulin which impairs a person's ability to regulate blood glucose normally.
What is the technical term for diabetes?
What does it mean?
Diabetes Melitus
Melitus is latin for 'sugar in the urine'
What is pre-diabetes?
condition in which blood glucose levels are higher than normal but not high enough to be diagnosed as diabetes; considered a major risk factor for future diabetes and CV diseases.
Where does diabetes mellitus rank as a cause of death in the US?
How much does it cost us per year?
$132 billion
How many adults ages 20 and over in the US have prediabetes?
How many adults in the US have diabetes?
Prediabetes = 57 million
Diabetes = 24 million
What is Insulin Resistance?
What causes it?
1.A condition in which a normal or high level of circulating insulin produces a less than normal response in muscle, liver, and adipose tissues.
2. Thought to be a metabolic consequence of obesity.
What is type I dibetes?
Type I diabetes = type of diabetes in which the pancreas produces no or very little insulin.
- often diagnosed in childhood (juvenile diabetes)
What is the leading chronic disease amoung juveniles and adolescents?
Type 1 Diabetes
What are the percentage rates for Type 1 Diabetes and Type 2 Diabetes?
Type 1 = 5-10%
Type 2 = 90-95%
What is an Auto Immune Disorder?
What are 2 examples?
Auto Immune Disorder = A disease in which the body develops antibodies to it's own proteins and then proceeds to destroy cells containing these proteins.
Examples = Diabetes 1 and lupus.
Why is Insulin injected and not taken orally?
The digestive system would digest insulin.
T or F, Genetic Inheritance is not a factor in Type 1 diabetes.
False, Genetic Inheritance IS a factor in Type 1
What organ is attacked in Type 1 Diabetes?
The Pancreas
Define Type 2 Diabetes
What are 2 former names?
The type of Diabetes in which the pancrease make plenty of insulin but the bodies cells resist insulin action.
AKA adult onset diabetes or nonisulin diabetes.
T or F, a low carbohydrate diet (less than 130 g) is reccomended for those with Type 2 diabetes.
What plays a centrol role in controlling blood glucose as far as diet is concerned?
Controlling Carbohydrate Intake.
Added Sugars
any sugar extracted from it's original source and added to foods.
how many calories and CHO does a teaspoonful of any sweet supply?
About 16 calories and 4 g of CHO
T or F, brown colored grains are always multigrains.
False, they can be refined with color added to them.
How much CHO do oils and solid fats contain?
What is brown sugar?
White sugar with molasses added.
95% pure sucrose.
What is confectioners sugar?
99.9% pure sucrose
What is dextrose?
An older name for sucrose
What is high fructose corn syrup?
a commercial sweetener used in many foods, indluding soft drinks.
comosed almost entirely of monosaccharides fructose and glucose.
What is white sugar?
Pure sucrose, produce by dissolving, concentrating, and recrystalizing raw sugar.
What 2 sugars primarily make up High Fructose Corn Syrup?
Fructose and Glucose
What is starch almost entirely composed of?

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