Important

MACROMOLECULES(“Large Molecules”)

Used in Biological Systems:

Carbohydrates

Lipids

Proteins

Nucleic Acids

What Are They???

Carbohydrates, Lipids, Proteins, and Nucleic Acids are the 4 major classes of organic compounds in cells.

Because these are very large molecules and very important in Biological Systems, we refer to these 4 classes of organic compounds as the MACROmolecules of Life.

Important Terminology

Compound: Two or more DIFFERENT molecules combined.

Example: Water molecules bound together with hydrogen bonds are NOT compoundsExample: Sucrose (table sugar) is a compound. (More than one type of molecule present.

Mixture: Two or more DIFFERENT compounds combined.

Organic: Any molecule that contains a carbon atom.

**All of the macromolecules discussed in this presentation are organic**

Monomer: Simplest single-carbon component of a compound or macromolecule.

Dimer:Two monomers combined.

Polymer:Many monomers combined to form a large “macro” molecule

Important Terminology (cont.)

Composition of MacromoleculesElements Involved:

CarbonHydrogenOxygenNitrogenPhosphorous

Formulas:Carbohydrates = CH2OLipids = CHOProteins = CHONNucleic Acids = CHONP

ALL OF THESE MACROMOLECULES ARE ORGANIC

Monomers Involved:1. Carbohydrates: monosaccharides

2. Lipids: glycerol and fatty acids

3. Proteins: Amino AcidsThere are 20 Amino Acids used to make proteins in mammals.

4. Nucleic Acids: NucleotidesNucleotides consist of a nitrogenous base, a phosphate group and a ribose sugar. There are 5 known nucleotides.

Composition of Macromolecules(continued)

CARBOHYDRATES (CH2O)

Monomers of carbohydrates: Monosaccharides

Carbon Water (C6H12O6 ==> CH2O)

Carbohydrates are Sugars!Saccharide = greek word for sugar

Where saccharin (artificial sweetener) got its name

Carbohydrates Carbohydrates usuallyusually end with the end with the ––ose suffixose suffix

One saccharide moleculeaka Simple sugarsmonomers that comprise carbohydrates

Examples: Glucose – used in Cellular RespirationFructose – fruit sugar Galactose – part of Milk sugarRibose – part of DNA and RNA molecules

Classification (Forms) of Carbs

Monosaccharide

Disaccharide Two monosaccharides combined

Examples: » Sucrose = Glucose + Fructose (table sugar)

» Maltose = Glucose + Glucose

(malted milk balls, ice cream malts)

» Lactose = Glucose + Galactose (milk sugar; lactation)

Classification (Forms) of Carbs (cont.)

Polysaccharide Many monosaccharides combined

Very large molecules

Complex Carbohydrates

Examples:»Glycogen – NRG storage in mammals»Starch – NRG stored in plants; Pasta»Cellulose – Paper; humans can’t digest

Long chains of glucose

Classification (Forms) of Carbs (cont.)

Uses of carbohydrates

Used as a primary source of NRG in humans.Strength and Rigidity in plantsSweetenerPaperThickenersExample of Medical use:

Heparin (polysaccharide) » (Hep-lock)

• Used to prevent excessive blood clotting when administering IV fluids in hospitals

LIPIDS (CHO)Monomers of Lipids:

Fatty Acids and glycerol

Lipids are Fats!

Basic Elements:CHO

Some Lipids are called “saturated” and some are called “Unsaturated.”

Saturated: All 4 of Carbon’s possible binding sites are bound by atoms. These are solids at room temperature. (Examples: Vaseline, Wax, Shortening)

Unsaturated: Not all of Carbon’s possible binding sites are bound by other atoms. Carbon will then form double bonds with other Carbon atoms. These are liquids at room temperature (Examples: Cooking Oil, gasoline)

Forms of LipidsTriglyceride = glycerol + fatty acid chains

Lipids are stored in humans as triglyceridesFatty acids have two regions

» Hydrocarbon chain» Carboxyl group (COOH)

SteroidsCholesterolBile saltsMale and female sex hormones

– Estrogen and Progesterone– Testosterone

Wax Phosopholipid – Part of Cell membrane

ProstaglandinsRaise and lower blood pressureContract smooth muscle (blood vessels, intestines)

Uses of Lipids

Used as a Secondary source of energy in humansConstruction of Cell MembranesHelps to maintain Homeostasis (prostaglandins)Protective Coatings

Waterproofing agents; Car Wax

CookingPetroleum Products

Gasoline; Paint Thinner; Vaseline

Candles

PROTEINS (CHON)Monomers of proteins: Amino Acids

Basic Elemental Components: CHON

20 Amino Acids found in MammalsExample of amino acids:

GlycineLeucine

Amino acids Amino acids usuallyusually end in –INE end in –INE

PROTEINS & AMINO ACIDS• Single carbon amino acids = Peptides

– Peptides are bound together to make DIPEPTIDES (2 peptides) or POLYPEPTIDES, (more than 2).

• The covalent bond between 2 peptides is called a Peptide BOND.

• Proteins are chains of amino acids AND

Polypeptides are chains of amino acids!•PROTEINS = POLYPEPTIDES!!!

Leu

Phe

Trp

Met

Lys

More on ProteinsProteins are Temperature dependent!

High temperatures will “Denature” proteins, which means they will break down, lose their shape, and cease to function

Low Temperatures cause proteins such as enzymes to function less efficiently. The Optimal temperature for Protein function is body temperature.

Body temperature is 98.6F or ~32CExample:

Fevers are dangerous because proteins such as enzymes will stop functioning if temperature goes to high

Fresh vs. Canned Pineapple in Gelatin» Enzyme (Bromelain) found in fresh pineapple breaks down

protein» Gelatin is a Protein.» Mix fresh pineapple in Gelatin: Gelatin won’t set» Use canned pineapple: Gelatin will set. Why?

• Pineapple is heated during process of canning, which denatures bromelain

Forms of Proteins

Enzymes = ProteinsAct as catalysts for bodily reactions, which help reactions occur easier, faster, and with less energy.

Plant Proteins: Gluten Example: Whey and Soy Protein

Enzyme and Substrate

Muscle tissue:Proteins are stored in the body as muscle tissueLast energy reserve but can be used as an NRG source if

neither Carbohydrates nor Lipids are available.

Uses and Examples of Proteins

Tertiary Energy Source in HumansFacilitate Reactions (Enzymes)Aid in Digestion (Enzymes)Coded for by DNA and RNAExamples (Forms):

Insulin» Some diabetics don’t produce this

Lactase» People who are Lactose Intolerant don’t produce this

Amylase» Found in saliva; breaks starch into individual glucose» Makes potatoes sweet if you keep them in your mouth long

enough

NUCLEIC ACIDS (CHONP)Monomers of Nucleic Acids: NucleotidesElements: Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorous

Five nucleotides; Four in each of the nucleic acids DNA and RNA

CytosineThymineAdenineGuanineUracil(replaces thymine in RNA)

FORMS: DNA and RNAWhat does DNA and RNA stand for?

DNA= Deoxyribonucleic AcidRNA= Ribonucleic Acid

FUNCTION: Stores Genetic information that codes for all the proteins in your body.

Used as a template or blue-prints to build proteins.