Enzymes & Macromolecules

ProteinsNucleic AcidLipidsCarbohydrates

Role of Carbon in Organic Compounds

Carbon is found in

all living organisms. It can form up to 4 bonds with other elements or compounds.

Carbon Is Unique

* Four electrons in outer shell; bonds with up to four other atoms (Usually H, O, N, or other carbons).

* Can bond to itself making chains and rings (back bones of organic molecules).

* Characteristics allow it to form an enormous variety of organic molecules.

CARBON ATOM

Monomers & Polymers

A. Monomer : Are small units that bind together to make large molecules. (Polymer) A polymer can be a straight chain or have many branching chains that fold back on itself.

B. There are Four Major Classifications of Polymers in Biology : Carbohydrates, Lipids, Nucleic Acids, and Proteins

Monomer

PolymerPolymer Polymer Polymer

Classes of Polymers

Carbohydrates (Polysaccharides)Lipids (Triglycerides)

Proteins (Polypeptides)Nucleic Acids

Building a Polymer(Dehydration Synthesis)

Polymers (carbohydrates, fats, proteins and nucleic acids) are built by bonding monomers together.

The joining is called dehydration synthesis. (Sometimes condensation).

REMOVE WATER!

Building a Polymer Chain(Remove water!)

Dehydration synthesis

Breaking Down A Polymer(Hydrolysis)

Hydrolysis means to split with water.“water” (hydro–)“split” (–lysis)

ADD WATER!

Breaking a Polymer Chain(Add Water!)

Organic Compound:Carbohydrates

GLUCOSE

1. Carbohydrates (sugars) : Basic monomer looks like this :

Carbohydrates : (sugars) Always have carbon, hydrogen, and oxygen. (CH2O)n Almost all carbohydrates are Hydrophilic.

Simple sugars with a backbone of three to seven carbon atoms.

Best known monosaccharides sugars have six carbons (hexoses).

GlucoseFructoseGalactose

Monosaccharides(Single Sugars)

Dissacharides(Double Sugars)

Two monosaccharide (single sugars) joined by dehydration synthesis. -Lactose Galactose + Glucose

Found in milk.-Maltose Glucose + Glucose

Forms in human digestive tract during starch digestion.-Sucrose Glucose + Fructose

Transported within plants.

Polysaccharides

Chains of glucose molecules or modified glucose molecules.

Polysaccharides(carbohydrates) Used For Energy Storage

Starch.Found in plants.Straight chain of glucose moleculesFew side branches.

Glycogen.Found in animals (called “animal starch”).Highly branched polymer of glucoseMany side branches

Cellulose - Not easily digested due to the strong linkage between glucose molecules. Cellulose glucose bonded to form mcrofibrils; primary constituent of plants cell walls.

– Grazing animals can digest cellulose due to special stomachs and bacteria.

– Cotton - nearly pure cellulose.

Polysaccharides(carbohydrates) Structural Forms

Organic Compound:Lipids

FATTY ACIDA lipid unit molecule

Fatty acid - long hydrocarbon chain, carboxyl (-COOH), [acid] group at one end.

Carboxyl group is polar, fatty acids are soluble in water.

Most fatty acids in cells contain 16 to 18 carbons atoms per molecule.

FATTY ACID

Saturated Only single bonds between atoms. (NO doubles)

Unstaturated Double bonds in the carbon chain where there are less than two hydrogens per carbon atom.

WAXES

• Fatty acids bonded alcohol instead of glycerol.• Solid at room temperature• High melting point • Waterproof • Resist degradation.• Form protective coverings

– Retards water loss in plants– Maintain animal skin and fur.

Phosphate group is the polar head; hydrocarbon chains become nonpolar tails.

PHOSPHOLIPIDS In aqueous environments, arrange in a double

layer. Polar (hydrophilic) heads toward water molecules.

Nonpolar (hydrophobic) tails face toward each other - away from water molecules.

Very important property!

Forms an interface or separation between two solutions (e.g. The interior and exterior of a cell

Phospholipid bilayer

STEROIDS

Cholesterol part of an animal cell membrane.Used to make other steroids.

STEROIDS

Testosterone is the male sex hormone.Progesterone is the female sex hormone.

Organic Compound:Proteins

Proteins

 

FunctionsForm cell structuresChemical messengers EnzymesBody defenseRegulationMovement & support

Monomersamino acids

Polymers PolypeptidesProteins

Amino Acids

R C

H

C

NH2

O

OH

Carboxyl groupamino group

Denaturation Of Proteins

Loss of normal shape – a physical change.

Once a protein loses it normal shape, it cannot perform its usual function.

How Proteins Can Be Denatured

• TemperatureCooking an eggAlbumin congeals

• Addition of hydrogen or hydroxide ions (large pH changes)

Adding acid to milkCauses curdling

• Vigorous Shaking – making whipped cream• Organic Solvents• Salts of heavy metals (mercury, silver & lead)• Detergents• Ultraviolet Radiation

Degradation Reaction(Hydrolysis for example)

Factors Affecting Enzyme-Catalyzed Reaction Rates

• Substrate Concentration• Enzyme Concentration• Temperature (optimum)• pH (optimum)

Animation Of Enzymes

Specific Animation Of Enzymes

Chemistry in BiologyChapter 6

Organic Compound:Nucleic Acids

4. Nucleic Acids : Found in DNA & RNA. Are made of a Phosphate, Sugar, and a Nitrogen Base. (Nucleotide) DNA is doubled strained and RNA is Single strained.

Tests for Organic Macromolecules