A TASTE FOR TROUBLE
A Case Study of Nutritional Health as an introduction to
Macromolecules for High School Biology Classes
Nutrition Labels
• In the early 13th century, the king of England proclaimed the first food regulatory law, the Assize of Bread, which prohibited bakers from mixing ground peas and beans into bread dough.
First Food Label
• 1990 Nutrition Labeling and Education Act (NLEA) is passed. It requires all packaged foods to bear nutrition labeling and all health claims for foods to be consistent with terms defined by the Secretary of Health and Human Services.
New laws continue to be passed to further educate
and inform consumers about
the foods they buy.
For Example:
• 2004 Passage of the Food Allergy Labeling and Consumer Protection Act. Requires labeling of any food that contains one or more of: peanuts, soybeans, cow’s milk, eggs, fish, crustacean shellfish, tree nuts, and wheat.
FDA Food Labels Have the Same Format
Fast Fact
Severely obese children aged 6-10 are now dying from heart attacks caused by their weight.
Fast Fact from Healthtrek.org a program of Group Health Community Foundation
Some manufacturers have implemented
their own food information labels
misleading customers into thinking they are
buying a nutritious product.
Macromolecules 101
11
Carbon Bonding
12
Large Carbon Molecules
• Monomer: small, simple Carbon molecule– Building blocks– 6 carbon rings
• Polymer: repeated, linked monomers• Macromolecule: large polymer– Ex: carbohydrates, nucleic acids, lipids,
proteins.
13
Dehydration & Hydrolysis
• Dehydration: water molecule is released when a monomer bonds to another monomer (or polymer)
• When building bonds• Also called condensation reactions
• Hydrolysis: water molecules are used to break down a polymer
• When breaking bonds• Energy is released when breaking bonds
14
Dehydration• Each Carbon in monomers have 4
bonds already (stable)–What must be done to bond to
another carbon monomer? • Break bonds to make bonds• Lose a water molecule
15
Macromolecules
• Formed via dehydration reactions• Monomers bond together form
polymers• Monomers bonded to polymers to
form macromolecules• 4 types:– Carbohydrates– Proteins– Lipids– Nucleic Acids
16
Carbohydrates• Composed of: C, H, O• Function: Source of energy &
structural material for organisms• Structure: basic ring
structure– Can exist as monosaccharides,
disaccharides, and polysaccharides
• Monomer of a carbohydrate is a monosaccharide.
17
Proteins• Composed of: C, H, O, N• Function: enzymes, build muscle,
hair, horns, and skin• Structure:
• Central carbon• Carboxyl group• Amine group•Hydrogen• R group
• Monomer of a protein is an amino acid– 20 different Amino Acids
18
Proteins• R group–Think of it as the “Rest” of the molecule handing off the amino acid “Backbone”• Influences the characteristics and chemical
reaction of molecules that they compose
–Create the variety among amino acids• Ex: -OH (hydroxyl) group makes the molecule
polar
19
Lipids• Composed of: C, H, O Function: storage of energy, protection (waxy
coating), steroids
• Structure:– Carboxyl (COOH) (polar head)– Long carbon chain (nonpolar tail)
• Monomer of a lipid is a fatty acid
• C-C and C-H bonds are high energy– Lipids store more energy than other organic
molecules
20
Nucleic Acids
• Composed of: C, N, P, O• Function: store & transfer
information, direct cell activities, manufacture proteins
• Structure:• Phosphate Group• Carbon (Sugar)• Nitrogenous base
• Monomer of a nucleic acid is a nucleotide
Using Everyday Items to Estimate
Portion SizeWoman's fist or baseball -serving of vegetables or fruit is about the size of your fist
Rounded handful - about one half cup cooked or raw veggies or cut fruit, a piece of fruit, or ½ cup of cooked rice or pasta - this is a good measure for a snack serving, such as chips or pretzels
Using Everyday Items to Estimate
Portion SizeDeck of cards - a serving of meat, fish or poultry or the palm of your hand (don't count your fingers!) - for example, one chicken breast, ¼ pound hamburger patty or a medium pork chop
Golf ball or large egg - one quarter cup of dried fruit or nuts
Tennis ball - about one half cup of ice cream,
Using Everyday Items to Estimate
Portion SizeComputer mouse - about the size of a small baked potato
Compact disc - about the size of one serving of pancake or small waffle
Thumb tip - about one teaspoon of peanut butter
Six dice - a serving of cheese
Check book - a serving of fish (approximately 3 oz.)"
http://www.mealsmatter.org/EatingForHealth/Topics/article.aspx?articleID=52