NUTRITION EXAM 2 - carbohydrates

glycogen

**storage form of glucose in animals & humans -made and stored in liver & muscle -more complex and branched than starch -enzymes can attack all branches simultaneously -occurs through condensation reaction (2 come together, water released)

lactose intolerance

*CHO issue -inability to digest lactose due to lack of the enyzme lactase (intestinal villi damage - disease, malnutrition, medications, prolonged diarrhea) -inherited or acquired -lactose molecules REMAIN in the intestine attracting H20 -> discomfort, cramping, etc.

hydrolysis

*breaks down (most of digestion) breaks a disaccharide in two - USES H2O

condensation

*builds-up links 2 monosaccharides together - RELEASES H2O "dehydration reaction

phytates found in fiber are

*can bind some minerals (Zn, Fe, Ca) -found in grainy substances (husks of grains), legumes, and seeds

milk allergy

*different from lactose intolerance -an immune response to the protein in milk *protein issue

sucrose

*glucose + fructose -table sugar -occurs naturally-fruit

lactose

*glucose + galactose -30-50% of milk energy

maltose

*glucose + glucose -malt sugar -used in germination of seeds, barley

insoluble fibers

*help potty! -tough/fibrous -DO NOT dissolve in water -fermentable fibers: are digested by colon bacteria (soluble fibers are more fermentable) -help w GI health -prevents colon cancer, appendicitis, diverticulitis, hemorrhoids

viscous/soluble fibers

*lower cholestrol, good for heart, bind-you-up! -DISSOLVE in water to form gel -decrease cholesterol: binds bile acids -used to treat diarrhea -delays gastric emptying which makes feel fuller -decreases the rate of glucose absorption (diabetes) -digested by bacteria in the colon

starch

*richest food source = grains -polysaccharide in plants -serves as a storage form of glucose in plants -long, branched or unbranched chains of hundreds of thousands of glucose molecules -major food energy source worldwide

low blood glucose

*signals pancreas to SECRETE GLUCAGON into the blood -glucagon -> stimulates break down of glycogen from the liver, release of glucose into the blood

high blood glucose

*signals pancreas to SECRETE INSULIN into the blood -insulin -> stimulates uptake of glucose from the blood into cells, storage of glycogen in the liver and muscles, converts excess glucose into fat for storage

glucose

-also called dextrose -not as sweet -measured in blood as blood sugar or glucose

making glucose from protein

-amino acid conversion -gluconeogenesis

if glucose levels are high, ______ in pancreas secrete ______

-beta cells -insulin

examples of fibers

-cellulose -hemicellulose -pectins -gums -mucilages -lignins

polysaccharides

-composed mainly of glucose units -should contribute 45-60% of caloric intake

glucose for energy

-fuels most of body's cells -preferred source for brain, nerve cells, and developing red blood cells -cellular breakdown of glucose

CHO digestion

-occurs in small intestine, starts in mouth!

galactose

-seldom free in nature -part of lactose (milk sugar)

muscle storage

-selfishly hoards glycogen (1/3 in muscle, 1/4 in liver) *lots more in muscle than liver *more muscle = more storage

fiber

-structural part of plants -whole grains, veg, fruit, legumes -bonds between glucose units are UNABLE to be broken -polysaccharides that are not digested by human digestive enzymes -energy contribution is negligible -phytates

fructose

-sweetest sugar -fruit suagr -pentagon shape (5 sides)

a monosaccharide contains how many saccharide molecules

1

a disaccharide contains how many saccharide molecules

2

glucose is a ____ carbon structure

6

can fiber enzymes be broken down?

NO! -differ from starch, body can breakdown starch

TRUE/FALSE: glucose and fructose are handled essentially the same way in the body

TRUE

TRUE/FALSE: glycogen is MORE branched than starch

TRUE

TRUE/FALSE: rapid increase may cause discomfort

TRUE

TRUE/FALSE: fiber in foods is preferable to supplements

TRUE *whole foods = more nutrients!!!

what is insulin

a hormone that acts to take glucose out of the blood and deposit it into cells

goal of CHO digestion is the _____ of glucose

absorption

activity of salivary enzyme diminishes in the stomach due to stomach ____

acid

what happens if there is not enough CHO in diet?

body will use its own muscle & protein for brain

G-WORD: glycolysis

break down of glucose

G-WORD: glyconeogenesis

build-up of new glucose (condensation reactions)

2 overall types of fibers:

dietary fibers & functional fibers

G-WORD: glucose

energy

pancreatic amylase

enzyme that breaks down starches!

functional fibers

fiber is used as a supplement

the large intestine digests

fibers

what does the liver convert?

fructose and galactose to: glucose -monosaccharides broken-down into individual units -> go to portal vein to liver & absorbed by the bloodstream -> converted to glucose

the 3 monosaccharides are

fructose, glucose, galactose

what do all CHOs breakdown to?

glucose!

benefit of fiber unable to breakdown bonds between glucose units

go through unabsorbed, go through fiberous, keep us regular for #2 -eat fiber to keep regular, people become short of minerals if do not

constipation treatment

increase water & increase fiber *too much is not better than too little - can bind! (Zn, Fe, Ca)

ppl who are lactose intolerant are at risk for

insufficient intake of calcium

lactase breaks down

lactose

a condensation reaction:

links two monosaccharides together to form a disaccharide

what is gluconeogenesis

makes new glucose from non-CHO source (ex. protein)

maltase breaks down

maltose

a polysaccharide contains how many saccharide molecules

many

G-WORD: galactose

milk products - lactose

disaccharides are a pair of _____

monosaccharides

simple sugars

monosaccharides and disaccharides

CHO digestion starts in the ___

mouth

what is the key player that controls blood sugar

pancreas!

complex sugars

polysaccharides

dietary fibers

remain from food after passage through GI tract

a monosaccharide consists of a ___ ring

single

if fiber is present in the stomach, it _____ gastric emptying

slows

the 2 types of polysaccharides

starch, glycogen

G-WORD: glycogen

storage form of glucose

sucrase breaks down

sucrose

the 3 disaccharides are

sucrose, lactose, maltose

carbohydrate goal

supply energy by conversion to glucose "blood sugar" to be absorbed

2 types of dietary fibers:

viscous/soluble fibers & insoluble fibers