Biological Molecules

John IrelandChapter 3

Bio162

Carbon,The Organics

Carbohydrates NucleicAcids

Proteins Lipids

Carbon, the Organic Element

Biological Molecules

are Organic

Functional Groups, subunits of structure

Hydroxyl (-OH)

Carboxyl (-COOH)

Amino (-NH2)

Sulfhydryl (-SH)

Phosphate (PO4)

Methyl (-CH3)

Together these groups give organic molecules their functions

How do we go from small molecules to large polymers?

Dehydration Reaction

HHO HO H

How do we break them back apart?

Hydrolysis

HO H

HHO

Carbohydrates, the Sugars

Carbohydrates are polymers of Simple Sugars

Carbohydrates have two functions

Structural

Energy Storage

Function comes from Structure

Structure comes from the arrangement of monomers

New Arrangement = New Function

Nucleic Acids, Information

Nucleic Acids are polymers of nucleotides

Nucleic Acids have two functions

Heredity

Energy Transfer

Function is determined bythe order of nucleotides

Proteins, Diverse Functions

Proteins are linear polymers of amino acids

Amino Acids have an amino and a carboxylic acid functional group

There are twenty natural amino acids.

In essence, they are a chemistry tool kit.

Amino Acids bind together by peptide bonds

Proteins are extremely varied in Function

Function is derived from Structure

Structure is an emergent property.

There are four levels of structure.

Now pull them together…

Evolution likes to reuse what works.

A protein’s function is destroyed if the structure is destroyed (denatured).

Lipids, Diverse Structures

Lipids are polymers composed of the monomer acetyl-CoA

Very diverse structures can be formed.

Trigylceride

Phospholipid

Sterols/Steroids

Lipids have three functions

Structural

Long-Term Energy Storage

Signaling