Ch 3: Biomolecules

Ch 3: Biomolecules Organic compounds ? contain Carbon Based Very Diverse Group ? 4 major H,O,N,C….leads to millions of types of molecules Carbon has 4 Valence electrons So can covalently bond to? Up to 4 elements, including itself When with H…

Reasons For Diversity: Can Bond with other Carbons to form…. Chains Branched Chains Rings

Ring Structure Aromatic Compounds = Double bond somewhere Ex: Benzene C6H6

Ring Structure Aliphatic Compounds = Only Single Bonds Ex: Cyclohexane C6H12

Reasons For Diversity: Varied Bonding Patterns (Single, double, triple) Hydrocarbons Alkane Single Alkene Double Alkyne Triple

Same molecular formula, different structural formula Reasons For Diversity: Biomolecules exist as isomers. Same molecular formula, different structural formula Importance in Biology? FORM DRIVES FUNCTION!!

Reasons For Diversity: Biomolecules exist as isomers. C5H12 Same molecular formula, different structurally = different properties

P/S: 4 main macromolecules, and their monomers?

Proteins Nucleic Acids Carbohydrates Lipids Amino Acids (20) Nucleotides DNA/RNA Carbohydrates Monosaccharides Sugars Lipids Fatty Acids

Reasons For Diversity: 4. Functional Groups Adds to the diversity of biomolecules by replacing an H atom or a methyl group (-CH3) Ex: Hydrocarbon vs alcohol

Reasons For Diversity: 4. Functional Groups Provides a “Fingerprint” which classifies a compound Helps to “Predict” how compounds will act in a chemical reaction Makes molecules more reactive Where new bonds are formed and broken WHERE THE ACTION IS! Functional Group Practice

Carbonyl C=O

Carbohydrates C,H,O 2:1 Energy! Sugars ‘___ose’ ‘simple’ = Monosaccharides Disaccharides (sucrose) Polysaccharides – Storage: Starch, glycogen, Structure: cellulose chitin- exoskeleton

Carbohydrate Functional Groups? Hydroxyl (-OH) Carbonyl (-C=O) Hexose, Pentose, Triose

Dehydration synthesis vs. hydrolysis Glycosidic Linkages: Dehydration Synthesis http:http://Formation of a disaccharide Dehydration synthesis vs. hydrolysis

Alpha vs Beta Glucose animation 1-4 linkage

Lipids Long term storage of energy Component of cell membrane structure Protective surface coating (plant cuticle) Insulation; nerve function (Animals) Basis for many hormones Composition? Functional Group? C,H,O *No Ratio H:O Carboxyl -COOH Waxes Phospholipids Steroids Fats and Oils (triglycerides)

Steroids 4 interconnected rings Natural…fyi Anabolic..fyi

*MAJOR component of all cell membranes “phospholipid bilayer” Amphipathic "amphi" = "both“ - dual nature -polar/non-polar) Hydrophobic Hydrophilic *MAJOR component of all cell membranes “phospholipid bilayer”

Phospholipid vs Triglyceride Structure

Formation of a triglyceride Ester Linkages Hydroxyl-carboxyl connection H2O Formation of a triglyceride

(Plant, fish fats- aka oils) ‘kinks’ in the structure Solid at room temp (Animal fats) tightly packed Liquid at room temp (Plant, fish fats- aka oils) ‘kinks’ in the structure (All single)

Proteins Most complex Primary elements? Functional groups? *Functions* C, H, O, ****N Functional groups? Carboxyl –COOH Amine -NH2 *Functions* *Forms* Building Blocks: Amino Acids- 20 common amino acids Characteristics of Amino Acids *FYI only…

Peptide Linkages http://www.biotopics.co.uk/as/aminocon.html

LEVELS of PROTEIN STRUCTURE 1 2 3 4 Peptide bonds Alpha,Beta Di-sulfide Bridges 4+ Tertiary Forms H-bonds R-group Interaction

Protein Structure and Function Structural framework Storage Movement: cellular and body Metabolism/Catalysis(Enzymes-Hormones) Transport Body Defense Beta

Globular and Fibrous Proteins   Fibrous Proteins Little or no tertiary structure. Long parallel polypeptide chains. Cross linkages at intervals forming long fibres or sheets. Usually insoluble. Many have structural roles. E.x- keratin in hair and the outer layer of skin, collagen (a connective tissue). -Actin/Myosin- movement Globular Proteins Have complex tertiary and sometimes quaternary structures. Folded into spherical (globular) shapes. Roles in metabolic reactions. E.g.- enzymes, hemoglobin, insulin. -antibodies/defense

Denatured Protein

The Amino Acids R-group- changes the shape and the function

Nucleic Acids

Phosphodiester Linkage