CHAPTER

3

biochemistry

Atomic Structure:Protons = Electrons = Neutrons = Mass = Valence Electrons =Currently unstable Needs to obtain, give, or share 4 electrons

to become stable.

METHANE

VERSATILITY OF CARBON

Can form single bonds,

double bonds, triple bonds, or a

combination those bonds.

2 Types of Hydrocarbons:1. Aromatics = contain a

benzene ring

2. Aliphatics = no benzene ring

Both of the above pictures demonstrate aromatic hydrocarbonssince they contain a benzene ring in their structure and contain

only hydrogen and carbon

Alkanes – aliphatic hydrocarbon with all single bonds

Alkenes – aliphatic hydrocarbon with at least one double bond

Alkynes – aliphatic hydrocarbon with at least one triple bond

1

43

2

= synthesis of polymer by removing water

= breakdown of polymer by adding water

INTRODUCTION AND REVIEW

What are organic compounds?

By what process do monomers become polymers?What has to be removed?

By what process do polymers become monomers?What has to be added?

There are 4 main groups of organic molecules essential to life: CARBOHYDRATES, PROTEINS, LIPIDS, and NUCLEIC ACIDS

CARBOHYDRATES

Elements =

Monomers =

Monosaccharides General Formula =

Have a carbonyl group (C double bonded to O) Straight chain or ring structure

GLUCOSE – FRUCTOSE - GALACTOSEIsomers = same formula, different structure

Formula = C6H12O6

DISACCHARIDES

Disaccharide means… 2 sugars are joined by what process? What had been removed to allow the

disaccharide to form? Sucrose (ordinary table sugar) = one glucose

and one fructose Lactose (milk sugar) = one glucose, one

galactose Maltose (malt sugar) = 2 glucose

DEHYDRATION SYNTHESIS (CONDENSATION REACTION) FOR SUCROSE

POLYSACCHARIDESMany sugars

Cellulose StarchMade by plants Made by plantsMakes up 50% of woodCell wall of plants GlycogenThousands of glucose Hundreds of

glucose branchedin a long chain Stored in animal cells

PROTEINS

Elements =

Common examples….

Monomers =

Many amino acids join in order to form a polymer

General Structure of an amino acid: Carboxyl groupAmino groupHydrogen‘R’ group

DIPEPTIDES

What is a dipeptide? Where is the

peptide bond? Dehydration

Synthesis or Hydrolysis??

POLYPEPTIDES

What is a polypeptide?? Dehydration synthesis or Hydrolysis??

Lock andKey

Model

LIPIDS

Elements = Groups of Lipids =

triglyceride, phospholipid, wax, steroid

Nonpolar (do not dissolve in water)

Store energy effectively in C-H bonds

FATTY ACIDS

SATURATED / UNSATURATED FATTY ACIDS

Monounsaturated vs. Polyunsaturated

Saturated fats are solid at room temperature

Unsaturated fats are liquid at room temperature (such as plant oils).

TRIGLYCERIDESA saturated or unsaturated triglyceride?

Before After

Unsaturated SaturatedLiquid SolidCis Trans

4 TYPES OF LIPIDSTriglycerides, Phospholipids, Waxes,

Steroids

Phospholipids = 2 fatty acids joined to glycerol

2 layers of phospholipids make up the cell membrane = lipid bilayer

Phospholipid bilayer = barrier between the inside and outside of the cell.

Most of the body is water, the cell membrane is lipid…..lipids do not dissolve in water, so barrier forms.

PHOSPHOLIPIDS

Glycerol with a phosphate and 2 fatty acids = PHOSPHOLIPID

PHOSPHOLIPID BILAYER (THE CELL MEMBRANE)

Head = polar, hydrophilic Tail = non-polar, hydrophobic

4 TYPES OF LIPIDSTriglycerides, Phospholipids, Waxes,

Steroids

Wax = carboxylic acid chain (fatty acid) joined to alcohol chain (-OH)

Wax = water-proof, protective covering

4 TYPES OF LIPIDSTriglycerides, Phospholipids, Waxes,

Steroids