Chapter 4 Flashcards
Whole grain
entire kernel including bran layers, germ and endosperm
Bran
protective layers of whole grains - concentrated source of dietary fibre
Germ
Plant embryo where sprouting occurs. Where the oils come from. Rich in vitamin E and contains protein, fibre, B vitamins, riboflavin, thiamin, B6
Endosperm
Everything but germ and bran. Starch and some vitamins and minerals
Fortified grains
Thiamin, riboflavin, niacin, iron, folate,. Do not contain vitamin E, magnesium, vitamin B6 ect. that were lost in processing.
3 most common monosaccarides
glucose, galactose, fructose, also deoxyribose, ribose
Glucose
most important sugar. circulates in the blood. can be broken down to provide energy, passed into the bloodstream for delivery to other tissues that can use it for energy or be stored in the liver as glycogen and to a lesser extent synthesized as fat.
Galactose
Important molecule in nervous tissue. combines with glucose to produce lactose.
Fructose
sweetest taste, found in fruit and veg, does not cause a rapid rise in blood sugar as other sugars but can cause high levels of lipids. Too much can cause diarrhea in children. Most abundant in high fructose corn syrup
Types of disaccharides
sucrose, lactose, maltose
Lactose
contributes to 40% of energy in human milk and 30% in cows milk, galactose
Maltose
glucose + fructose. made when starch breaks down.
Sucrose
glucose + fructose
Hydrolysis reaction
chemical reaction that breaks bonds of sugar molecules. Adding a H+ and an OH-
Condensation reaction
chemical reaction that bonds sugar molecules together
a release of H+ and OH- from molecule to produce H2O
Short chain polyaccharides
3-10 monosaccharides and are called ogliosaccharides. Some are not digested in the small intestine. All are digested in the colon where microflora break them down.. Can contribute to a healthy microflora
Examples of long chain polysaccharides
Glycogen in animals and fibre and starch in plants
Starch
Polysaccharides. Many glucose molecules molecules linked in straight or branching chains. Storage form of carbohydrates in plants. amylose + amylopectin. broken down into mono’s and transported to the liver by hepatic portal vein.
Glycogen
Polysaccharide made up of a many branched chain of glucose. Storage form of carbohydrate in animals. Stored in the muscles and liver. Not consumed in the diet bc is broke down in the muscle tissue of animals shortly after slaughter. 200-500g present in the body. Carbohydrate loading is often done in athletes to increase glycogen in muscle tissue before event.
Amylose
long straight chains of glucose molcule
Amylopectin
branched chains of glucose molecule
Fibre
complex carbohydrate and lignins. different types like dietary fibre, functional fibre and total fibre (dietary + functional)
Dietary fibre
fibre found in plants
Functional fibre
isolated from its plants source but often used to fortify foods
Soluble fibre
can be digested in the large intestine
small quantities can be absorbed
types include: pectin, gums, some hemicelluloses
found in apples, beans, seaweed
slows nutrient absorption and the absorption of glucose
Insoluble fibre
does not break down or dissolve. found in structural parts of plants like cell walls. includes: cellulose, hemicellulose, lignins. found in wheat, bran, rye bran, veg.
Lactose intolerane
not enough lactase. undigested lactose reaches the large intestine and draws water and metabolized by bacteria producing acid and gas. 70-80% of Eastern Europeans are lactose intolerant.
Substances not digested in the small intestine
soluble/insoluble fibres, some ogliosaccharides, resistant starch
Resistant starch
starch that escapes the digestion in the small intestine. cooking can affect digestion of certain starches bc it changes the composition of the molecule. ex. legumes, bananas, cold cooked potatoes, rice, pasta
Two sugar components of the formation of DNA and RNA
deoxyribose and ribose. can be synthesized in the body and not found in significant amounts in the diet.
After absorption, monosaccharides travel to the…..
liver via hepatic portal
Glycolisis
metabolic reaction in the cytosol of the cell that split glucose into 3-carbon pyruvate molecules yielding 2 ATP molecules.
Gluconeogenesis
Glucose synthesis from 3 carbon molecules like pyruvate. Occurs in the liver and kidney cells
Ketone
Molecules that are formed in the liver when there is not enough carbohydrate supply to break metabolize oxaloacetate which breaks down acetyl-CoA. Can be used as energy for tissues like the heart, muscle, and kidney.
Ketosis
Excess ketones that cannot be excreted in the urine can accumulate in the blood increasing the acidity. Symptoms range from headache, bad breath, dry mouth coma and death. Can occur in untreated diabetes.
Diabetes Mellitus
disease caused by either insufficient insulin production or decreased sensitivity of cells to insulin. Elevated blood glucose levels.
Hypoglycemia
A low blood glucose level, usually below 2.2 to 2,8 mmol/L of blood plasma
Gycemic response
the rate and duration of the rise in blood glucose that occurs after a particular food or meal is consumed
Blood glucose response curve
A curve that illustrates the change in blood glucose that occurs after consuming foods.
Glycemic index
A ranking of the effect on blood glucose of a food of a certain carbohydrate content relative to an equal amount of carbohydrate from which a reference food such as white bread or glucose. ex. Low GI food slows the rate which glucose is absorbed. High GI food speeds up the rate which glucose is absorbed.
A type of diabetes that cause by the autoimmune destruction of insulin-producing cells in the pancreas usually leading to absolute insulin deficiency. Accounts for only 10% of the diagnosed cases. aka. juvenile onset diabetes
Type 1 diabetes
The combination of beta cell disfunction and insulin resistant factors are the cause of this type of diabetes. Makes up 90% of cases.
Type 2 diabetes
Insulin sensitivity and beta cell disfunction.
A decreased sensitivity of cells in the muscles, liver, and adipose tissued. Since tissues to do uptake insulin as readily, the pancreas secretes large amount of insulin (beta cells). Over time the secretion of beta cells will decline and amounts may not be sufficient to maintain normal blood glucose levels.
Insulin
hormone made in the pancreas that allows the uptake of glucose in the body cells and stimulates protein and fat synthesis and glycogen in liver. The more insulin you produce the more fat you store
Gulcagon
a hormone made in the pancreas that stimulates the breakdown of liver glycogen and the synthesis of glucose to increase blood sugar.
Why is excessive thirst and urination a symptom of diabetes
Blood glucose levels rise so high that the kidneys excrete glucose, which draws fluid with it increasing vol. of urine
Why is blurred vision a symptom of diabetes.
Excess glucose enters the lens of the eye, drawing in water and causing lens to swell
How can fibre help reduce cholesterol.
Soluble fibres bind to cholesterol and bile in the GI tract and are excreted in the feces rather than reabsorbed. Insoluble fibre (cellulose and bran) do not have this effect.
Diverticulitis
when the sacs or pouches that protrude from the wall of the large intestine are enflamed.
Malignancy or metastasis
a mass of cells showing uncontrolled growth , a tendency to invade and damage surrounding tissues, and an ability to seed daughter cells growths to sites remote from the original growth.
Carconogens
cancer causing substances that either stimulate cells to divide or cause genetic mutations in cells.
ADI
Acceptable daily intake = an estimated amount of sweetener per kg of body weight that a individual can consume every day over a lifetime.
