1. Ch 2 - Biochemistry

2. INORGANIC COMPOUNDS lack carbon (with the exception of carbon dioxide) and tend to be simple, small molecules water, salts, most acids and bases

3. Water Important Properties: High heat capacity - prevents sudden change in body temp that could result from sun exposure, winter winds, vigorous exercise, etc Polarity/solvent properties - “universal solvent” allows chemicals to react in solution like blood plasma; also important in lubrication, saliva, serous fluids and synovial fluids Chemical Reactivity - hydrolysis reactions, water molecules added to bonds of foods or large molecules Cushioning - protective function, i.e. cerebrospinal fluid and amniotic fluid

4. Salts Most plentiful salts in body contain Ca and P, found in bones and teeth All salts in the body are electrolytes - dissociate into ions and conduct an electrical charge in solution Na and K ions are essential for nerve impulses Fe forms part of the hemoglobin molecules Ionic (electrolyte) balance is essential to homeostasis

5. Acids and Bases Acids - sour taste, release H+ ions, proton donors; hydrochloric acid, acetic acid, carbonic acid Bases - bitter taste, release OH-, proton acceptors; sodium hydroxide, bicarbonate Neutralization Rxn: Acid + Base --> Water + Salt pH scale, 0-14, 1 pH unit change = 10X change in [H+] Weak acids and bases are important buffers in body fluids

6. ORGANIC COMPOUNDS Carbon-containing compounds, large covalently bonded molecules Carbohydrates, Lipids, Proteins, and Nucleic Acids

7. Carbohydrates contain carbon, hydrogen, and oxygen; end in -ose usually in ratio of 1:2:1 (glucose is C6H12O6; ribose is C5H10O5) Glucose (blood sugar) is called the universal cellular fuel. 1 g carb= 4 Calories monosaccharide - one unit (simple sugars), single chain or single ring; glucose, fructose, galactose, ribose, deoxyribose disaccharide - double sugars; sucrose (glucose-fructose), lactose (glucose- galactose), maltose (glucose-glucose) polysaccharide - many sugars; long branching chains, used for storage (not sweet); starch (plants), glycogen (animals)

8. Carbohydrates

9. Dehydration synthesis and hydrolysis

10. Lipids most abundant lipids in body: fats, phospholipids, steroids carbon, hydrogen, and oxygen molecules (mostly C and H) building blocks: fatty acids and glycerol most are insoluble in water 1 g fat = 9 calories large amount of energy, insulation, protection saturated-animal fats, butter, lard, grease (solid at room temp) unsaturated-most plant oils, olive oil, fish oils (liquid at room temp)

11. Lipids Triglycerides (fats) - insulation and energy storage Phospholipids - main component in cell membranes Steroids - (cholesterol, Vit D, estrogen, cortisone) many functions - stimulate growth, develop repro organs, sexual function, anti-inflammatory, essential in brain function Waxes

12. Proteins building block = amino acids (C, H, O, N); amine group, acid group, and variable R-group (makes a.a. chemically unique) peptide = short chain of amino acids; polypeptide = long chain of a.a. Humans must have 20 different a.a., but can produce only 10, others must come from food Structure is VERY important for function - pH and temperature can affect shape Food sources: legumes, eggs, milk, fish, poultry, meat 1 g protein = 4 Calories

14. Protein Functions Over 50% of organic matter in body is protein structural or fibrous proteins (bones, ligaments, cartilage, tendons,skin) - collagen, keratin Globular or functional proteins: defense against infection - antibodies hormones - insulin, prolactin, nerve growth factor transport - hemoglobin histones - “spool” around which DNA winds ENZYMES - speed up chemical reactions in body, help break down molecules

15. Amino Acid Sequence One wrong a.a. sequence in the hemoglobin protein=mis-shapen RBC and severely limits function

16. Enzymes most end in -ase substrate = molecule the enzyme acts on active site = location where enzyme fits with substrate

17. Nucleic Acids made of nucleotides (pentose (5-C) sugar, phosphate group, nitrogen base); in all cells bases: adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U) deoxyribonucleic acid (DNA) - double helix; genetic material; replicates itself; provides instruction for building every protein in body A- T, G-C ribonucleic acid (RNA) - single strand; makes proteins in the cell A-U, G-C

18. Adenosine Triphosphate (ATP) form of energy used by all cells modified nucleotide: adenosine base, ribose sugar, three phosphate groups when glucose is oxidized, energy is captured by ATP and stored high-energy phosphate bonds are hydrolyzed to release energy to do work