do now make a list of foods that you eat and categorize them how will you categorize? why? what...

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Do Now Make a list of foods that you eat

and categorize them

How will you categorize? Why?

What is in each one?

Prefixes and Suffixes to know

carbo- =“coal”

di- = “two”

hydro- =“water”

mono- =“one”

poly- =“much”

-ase = “enzyme”

-hydrate = “water”

-ose =“sugar”

-philic = “loving”

-phobic =“fearing”

-saccharide = “sugar”

Organic Molecules organic molecules: carbon based molecules

Carbon can form bonds with one or more other carbon atoms, producing an endless variety of carbon skeletons

hydrocarbons: composed of only carbon and hydrogen Important as fuels

Methane (CH4) - natural gas Energy-storing fat molecules

Inorganic Molecules

inorganic molecules: non-carbon based Ex. Water, O2,

NH3

Functional Groups functional groups: group

of atoms within a molecules that interact in predictable ways with other molecules

Hydroxyl group Called alcohols Polar Soluble in water

Carbonyl group Ketones and aldehydes Polar Some sugars

Carboxyl group Carboxylic acids Polar and soluble Acidic In amino acids

Amino groups Amino acids Slightly polar basic

Monomers and Polymers

monomers: small molecular units form a larger similar combination of hundreds or millions of atoms

polymers: long chains of repeating monomers Branching chains or folding Every living cell has thousands

of different kinds Made from a collection of fewer

than 50 kinds of monomers

4 main categories Carbohydrates -- Proteins Lipids -- Nucleic

acids

Building and Breaking Polymers

dehydration reaction: each time a monomer is added to a chain, a water molecule is released

hydrolysis reaction: water is added to a polymer to break it down Molecules in food are

polymers and need to be broken apart to be available to your cells

Monomers break down to obtain energy to make new polymers

5.2 Carbohydrates carbohydrate:

organic compound made up of sugar molecules

Sugars contain carbon, hydrogen and oxygen Ratio 1C:2H:1O Glucose= C6H12O6

Monosaccharides monosaccharide:

simple sugar that contains just one sugar unit Glucose, fructose

glucose: exists in straight-chain and ring-shaped forms Main fuel supply for

cellular work Unused molecules

are incorporated into larger carbs or to make fat

Disaccharides disaccharide:

“double sugar”; two monosaccharides combined by dehydration reaction

sucrose: most common; made of glucose and fructose Major carb in plant

sap and nourishes plants

Table sugar processed from sugar cane stems

Polysaccharides polysaccharide: long

polymer chains made up of simple sugar molecules Complex carbohydrates

glycogen: polysacch found in animals that act as a storage for excess sugar Chain of many glucose

monomers, but arte more highly branched than a starch monomer

In humans, most glycogen is stored as granules in liver and muscle cells and break down when the body needs energy

Plant Polysaccharides starch: found in plant

cells and consists entirely of glucose monomers Chains branch and coil up

in loops “sugar stockpile” =stored

energy

cellulose: serves at building materials; protect cells and stiffens plant Many glucose monomers Multiple chains are linked

by hydrogen bonds to form cable-like fibers in the tough plant cell walls

Does not dissolve in water

How to test for the presence of

carbohydrates in food Glucose:

glucose strip (easy) Benedict’s test: add Benedict’s

solution, place tube in boiling water for 5 minutes. Look for color change to red/brown

Starch Drop iodine on the product or

solution Changes to a purpleish black if

starch is present

Do Now Complete the Carbohydrates section of the chart

5.3 Lipids lipids: class of

compounds that is hydrophobic (water-fearing) Act as a boundary that

surrounds and contains the aqueous contents of your cells

Others circulate as chemical signals

Some are fats which store energy

Fats fats(triglyceride): a 3-carbon backbone(glycerol) attached

to 3 fatty acids(long hydrocarbon chains) Solid or liquid Fatty tissues cushion organs and provide body with insulation

saturated fats: all fatty acid chains contain the maximum possible number of hydrogen atoms All single bonds Solid at room temp Animal fats

unsaturated: less than max. number of H atoms in one ormore fatty acid chains Some double bonded Liquid at room temp. Most plant and fish oils

Steroids steroids: carbon

skeleton forms 4 fused rings Different functional

groups attached to rings

Different than fats in structure and function, but still hydrophobic

Cholesterol

Sex hormones

Cortisol

Vitamin D

Cholesterol cholesterol: essential

molecule found in cell membranes Starting point from

which your body produces other steroids

makes the lipid bilayer less deformable and decreases its permeability

Links to cardiovascular disease

LDL = low density lipoprotein “bad”

HDL = high density “good”

Triglycerides(fat)

Lipid Tests Paper Bag Test

Place the food on a paper bag Positive: leave a “stain” on the bag

Emulsion (Ethanol) Test Add the food sample to 2 cm3 of

ethanol, shake well. Allow to settle in a test tube rack for

2 minutes for food to dissolve in ethanol.

Empty any clear liquid into a test tube containing 2 cm3 of distilled H2O.

A MILKY-WHITE EMULSION is a positive result: lipid is present.

If the mixture remains clear, there are no fats present in the sample

Do Now

1. List 3 functions of proteins.

2. What foods are proteins found in?

3. What is the purpose of an enzyme?

5.4 Proteins protein: a polymer

constructed from a set of just 20 kinds of monomers called amino acids. responsible for

almost all of an organism’s functioning

Enzymatic, transport, structure, storage hormonal, receptor, contractile, defensive

Protein Structure amino acid: monomer that consists of a central carbon atom

bonded to four partners (carbon forms 4 bonds) three of the central carbon’s partners are the same in all amino

acids the “side group” or the “R-group” is responsible for the particular

chemical properties of each AA.

Polypeptide: chain of amino acids

that make up a protein dehydration reaction between amino group of one and a carboxyl of the next proteins = one or more polypeptide chains most chains are at least 100 AA

Shape polypeptides are

precisely twisted, folded, and coiled into a unique shape for each protein

influenced by the surrounding environment which is usually aqueous

hydrophilic and phobic to different sides

Denaturation Denaturation:

unfavorable change in pH, temperature, or other quality of the environment that causes the protein to unravel and lose shape (ex. frying an egg;

albumin is egg white which turns from clear to white)

Protein Test Biurets

To a test tube, add 40 drops of liquid to be tested.

If testing more than one liquid, label each test tube with a marker.

Add 3 drops of Biuret reagent solution to each test tube. Shake gently to mix.

Note any color change. Proteins will turn solution pink or purple.

Do Now What are enzymes made of?

What is the purpose of them?

5.5 Enzymes enzymes: specialized

proteins in organisms that exist as catalysts they provide a way for

chemical reactions to occur at normal temperature

does not supply activation energy, but it lowers the energy requirement barrier

each enzyme is specific to one reaction

Always recycled

pH and temp can affect function

Catalysts Catalysts:

compounds that speed up chemical reactions

activation energy: activates the reactants and triggers a chemical reaction “start-up” energy heat can provide

activation energy, but may cause other reactions

How Enzymes Work the shape of the enzyme

fits the shape of only particular reactant molecules

substrate - a specific reactant acted upon by an enzyme

active site - the substrate fits into a particular region of the enzyme can change shape slightly

to fit snugly will accept two substrates

into adjacent sites

Nucleic Acids

DNA: dexoyribose nucleic acid

RNA: ribose nucleic acid

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