Part 3: Organic Compounds Chemistry Comes Alive Part 3: Organic Compounds

Organic Compounds All contain C, H, O Types: Carbohydrates Lipids Proteins Nucleic acids (DNA, RNA) ATP

monomer  polymer  macromolecule Polymer: chainlike molecules made of repeating units called monomers Organic molecules are made by dehydration synthesis monomer  polymer  macromolecule

Polymers are broken down (digested) by hydrolysis

Carbohydrates Structure: contains C, H, O (C:H:O in 1:2:1 ratio) Function: main fuel for cells; some structure Types: Monosaccharides (monomers) – simple sugars Glucose, galactose, fructose, deoxyribose Disaccharides – double sugar glucose + fructose  sucrose Eg. lactose, maltose Polysaccharides – polymer (many sugars linked) Starch: storage carb in plants Glycogen: storage carb in animal tissues (liver, skeletal muscle)

Lipids Structure: contains C, H, O (much more CH than O) Function: store energy, cell membranes, hormones Types: Triglycerides: oils, fats Fatty acid + glycerol Saturated, unsaturated (mono- or poly-), trans, omega-3 Phospholipids: lipid bilayer in cell membranes Steroids: cholesterol, hormones Eicosanoids: prostaglandins (blood clotting, blood pressure, inflammation, labor)

Proteins Structure: contains C, H, O, N (+ some S, P) Functions: Monomer = amino acid Functions: Enzymes (lactase) Hormones (insulin) Transport (hemoglobin) Immunity (antibodies) Movement (muscles) Support (collagen)

Structural Levels of Proteins Primary: Amino acid sequence  forms polypeptide 20 different amino acids AA’s linked by peptide bonds

Structural Levels of Proteins Secondary: Hydrogen bonds make spirals and sheets Spirals = Alpha ()-helix Sheets = Beta ()-pleated sheet

Structural Levels of Proteins Tertiary: More folding to produce globular (compact, ball-like) molecule

Lysozyme

Structural Levels of Proteins Quaternary: 2+ polypeptides

amino acids  polypeptide  protein

Two Types of Proteins Fibrous Protein Structural Eg. collagen, keratin Globular Protein Functional Eg. antibodies, enzymes

Protein Denaturation Denature = protein unfolds and loses 3D shape Causes:  pH,  temperature Change in STRUCTURE  change in FUNCTION!!!

Nucleic Acids Nucleotide Structure: contains C, H, O, N, P Monomer = nucleotide (sugar, phosphate, nitrogen base) Function: store hereditary information Types: DNA, RNA Nucleotide

DNA RNA

DNA RNA Instructions for building proteins Double-stranded (double helix) Sugar: Deoxyribose Bases: A, G, C, Thymine Complimentary: A-T, G-C Carry info from DNA to ribosomes Single-stranded Sugar: Ribose Bases: A, G, C, Uracil mRNA, tRNA, rRNA

ATP (Adenosine Triphosphate) Structure: adenine base + ribose +3 phosphates Function: main energy compound of cells ATP  ADP + Pi + energy

Enzymes Biological Catalyst: speeds up chemical reactions, but not used up or changed Lowers activation energy (E required to start reaction)

Enzymes Substrate: what an enzyme acts on Active site: where substrate binds (very specific shape to fit substrate)

Enzymes Enzymes are proteins affected by pH and temperature

Protein Denaturation Denature = protein unfolds and loses 3D shape Causes:  pH,  temperature Change in STRUCTURE  change in FUNCTION!!!