Biological Molecules

Carbon

4 Single Valence Electrons (Tetravalent)

Organic Compounds

Carbon bonded to C&H carbon chains (Skeletons of organic molecules)

Structure determines…?

FUNCTION

Hydrocarbons

• Moleucules of ONLY C and H

• Nonpolar (no charge)

• Hydrophobic

Functional Groups

Change Molecular Function

Hydroxyl Group (R-OH)

• Alcohols (end with -ol)

• Polar

• Hydrophilic

• Neutral

Carbonyl Group (R-CHO)

• Aldehyde/Keytone

• Polar

• Hydrophilic (less than -OH)

• Neutral

Carboxyl Group (R-COOH)

• Carboxylic acids (H+ easily released)

• Polar

• Hydrophilic

• Acidic

Amino Group (R-NH₂)

• Amines (H+ easily accepted)

• Polar

• Hydrophilic

• Basic

Phosphate Group (R-PO₄H₂)

• Organic Phosphate

• Phospholipids/Nucleic Acids (DNA, RNA)

• Polar

• Hydrophilic

• Acidic

• Negative Charge

Methyl Group (R-CH₃)

• Methyl hydrocarbon

• Nonpolar

• Hydrophobic

• Neutral

• Controls Gene Expression

• Shape/Function of Sex Hormones

Monomers

Building blocks of Macromolecules

Polymers

Made of Monomers.

Ex:

• Carbohydrates

• Proteins

• Nucleic Acids

NOT LIPIDS

Dehydration Synthesis

• Remove Water to Build

• Enzyme used: Dehydrogenases

Hydrolysis

• Adds water to break a bond

• Enzyme used: Hydrolases

Carbohydrates

• Linear and ring form

• A or B Glucose; 2 ring formations

Glycosidic Linkage

Covalent bond between Monosaccharides

Dissaccharide

2 monomers

Ex: Sucrose= Glucose + Fructose

Polysaccharide

• >2 monomers.

• Sugar Polymers.

• Functions as energy OR Structural support

Lipids

• Hydrophobic

• NOT Polymers

• Hydrophilic Head, Hydrophobic Tail

• 3 Families: Fats, Phospholipids, Steroids

Fats

• Used as Energy Storage

• Consist of Glycerol: (3 carbon alcohol with 3-OH

• 1-3 fatty acids

Fatty acids + glycerol →

(via dehydration synthesis, water removed) → joined by covalent ester linkages → makes a fat

Double Bonds Determine if Fat is:

• Saturated Fatty Acid (Solid)

• Unsaturated Fatty Acid (Liquid)

• Trans Fatty Acid (Solid/Liquid)

Phospholipids

Cell Membranes

Amphipathic

Glycerol + 2 Fatty Acids (hydrophobic) phosphate group (hydrophilic)

Ex. Phospholipids

Steroids

3 rings of 6C and 1 ring of 5C
Used for hormones

Cholesterols

Used for communication and cell membrane structure

Cortisol

The stress hormone

Proteins

Most Important! Peptide bonds between amino acid (monomers)

Polypeptide

• Must to folded into the correct 3D shape to become a protein

• Determined by DNA

• R group does not participate

Primary Polypeptide Structure

Sequence of amino acids each bound to the next with a peptide bond

Secondary Polypeptide Structure

Within a single polypeptide, hydrogen bonds stick amino acids together

• A: Helix

• B: Pleaded sheet

Tertiary Structure

• Within a single polypeptide, R-groups interact and fold into a particular 3D shape

• All types of bonds

Quaternary Sturcture

• Multiple Polypeptide chains form one macromolecule (no more folding)

Denaturation

Loss of a protein’s 3rd or 4th structure

The denatured protein becomes inactive. Causes: pH, salt concentration and temp

Nucleic Acid

Monomers are Nucleotides

-DNA

-RNA

Transmit hereditary info and determine protein production

Renaturation

When a denatured protein refolds back into its correct shape to regain function