Biochemistry To be used with Biochemistry Guided Notes Gaccione/Bakka Homework • Page 34, 1 through 8 Organic vs. Inorganic Molecules Organic Inorganic Contains Carbon (C), Hydrogen (H), Does not contain C, H, and O and Oxygen (O) at same time (Example: H20) (Example: C6H12O6) Carbon is the key element— the element of life Carbon can bond with itself and form many times for bonds (single, double, triple and rings) Water: makes up 60 to 98% of living things—necessary for chemical activities and transport Salts: help maintain water balance Example: Gatorade—electrolytes 4 Organic Molecules: 1. Carbohydrates 2. Lipids 3.Proteins 4. Nucleic Acids Acids and Bases: -pH Scale -Important for enzyme function Carbohydrates give us instant energy • Sugars and starches(complex carbohydrates) • Contains 3 elements: carbon, hydrogen, and oxygen In all carbs the hydrogen is in a 2:1 ratio to oxygen) • Most carbohydrates end in -ose Monosaccharides - means one sugar • • • • AKA Simple sugars All have the formula C6H12O6 Have a single ring structure Example: Glucose Fructose Disaccharides - means two sugars • All have the formula C12H22O11 • Example: glucose + fructose = sucrose (table sugar) maltose Isomers • Example: Glucose & Galactose • Isomers - compounds that have same formula different 3-D structure Polysaccharides (polymers)means many sugars • Three or more simple sugar units • Examples: – Glycogen: animal starch stored in the liver and muscles – Cellulose: indigestible in humans: forms cell wall in plants – Starches: used as energy storage Comparing saccharides Monosaccharides Polysacchrides Disaccharides How are complex carbohydrates (polysaccharides) formed? • Condensation (Dehydration) synthesis: combining simple molecules to form a more complex one with the removal of water • Example: – monosaccharide + monosaccharide disaccharide + water – C6H12O6 + C6H12O6 C12H22O11 + H2O • Polysaccharides are formed from repeated dehydration synthesis Monosaccharide + Monosaccharide Disaccharide + Water How are complex carbohydrates broken down? • Hydrolysis: the addition of water to a compound to split it into smaller subunits – also called chemical digestion • Example: – disaccharide + water monosaccharide + monosaccharide – C12H22O11 + H2O C6H12O6 + C6H12O6 Lipids • Lipids (Fats): lipids 4 function 1. energy storage 2. protection 3. insulation 4. found in cell membranes • Three elements found in lipids 1. carbon 2. Hydrogen 3. oxygen The H:O is not in a 2:1 ratio Lipids – Examples: 1. meat 2. bacon 3. cheese • Lipids tend to be the largest of organic molecules Lipids • Lipids are composed of one glycerol molecule and 3 fatty acids Lipid formular • glycerol + 3 fatty acids lipid (fat) • Condensation (Dehydration) synthesis: combining simple molecules to form a lipid with the removal of water • Hydrolysis: the addition of water to a lipid splits it into smaller subunits Four Types of Lipids 1.Fats: from animals • Saturated: solid at room temperature • All single bonds in the fatty acid tail make it very difficult to break down 4 Types of Lipids 2. Oils: from plants • Unsaturated: liquid at room temperature • • Presence of a double bond in the fatty acid tail Ex. Vegetable oils Four Types of Lipids 3. Waxes: ear wax & bees wax 4 Types of Lipids 4. Steroids: • Examples: 1. Cholesterol - High levels could lead to heart disease 2. Estrogen - female hormone 3. Testosterone - male hormone Proteins • Proteins: contain the elements 1. carbon 2. hydrogen 3. oxygen 4. Nitrogen – Made at the ribosomes – Composed of subunits called amino acid – 20 amino acids Proteins • Major Protein Functions: Growth and repair & Energy • Usually end with -in: • Example: 1. Hemoglobin (blood) 2. Insulin (breaks down glycogen) 3. Enzymes(speeds up chemical reactions) Making Proteins • Condensation (Dehydration) synthesis of a dipeptide. Breaking down Proteins is call Hydrolysis dipeptide + water amino acid + amino acid • Dipeptide: formed from two amino acids • amino acid + amino acid dipeptide + water Proteins • Polypeptide: composed of three or more amino acids • Examples of proteins: 1. muscle 5. insulin 2. Skin 6. hemoglobin 3. Hair 7. enzymes 4. Nails • There are a large number of different types of proteins: – The number, kind and sequence of amino acids lead to this large variety Enzymes • Catalyst: inorganic or organic substance which speeds up the rate of a chemical reaction without entering the reaction itself – Examples: enzymes (organic) and heat (inorganic) • Enzymes: organic catalysts made of protein – most enzyme names end in –ase – enzymes lower the energy needed to start a chemical reaction (activation energy) How enzymes work 1. Enzyme forms a temporary association with a the substance it affects • These substances are known as substrates. 2. The association between enzyme and substrate is very specific—like a Lock and Key • This association is the enzyme-substrate complex 3. While the enzyme-substrate complex is formed, enzyme action takes place. 4. Upon completion of the reaction, the enzyme and product(s) separate 5. The enzyme is now able to be reused Enzyme-Substrate Complex Enzyme Terms • Active site: the pockets in an enzyme where substrate fits – Usually enzyme is larger than substrate • Substrate: molecules upon which an enzyme acts • All enzymes are proteins • Coenzyme: non-protein part attached to the main enzyme – Example: vitamins Proteins in action enzyme substrate -------------> product Lock and Key Model Factors Limiting Enzyme Action • pH: pH of the environment affects enzyme activity – Example: pepsin works best in a pH of 2 in stomach Amylase works best in a pH of 6.8 in mouth--saliva Factors Limiting Enzyme Action • Temperature: as the temperature increases the rate of enzymes increases – Optimum Temperature: temperature at which an enzyme is most affective • • Humans it is 37 degrees C or 98.6 degrees F Dogs between 101 and 102 F When Temperatures Get Too High • Denature: – Change in their shape so the enzyme active site no longer fits with the substrate – Enzyme can't function – Above 45 C or 130 F most enzymes are denatured • Why do we get a fever when we get sick? General Trend vs. Denaturing Factors Limiting Enzyme Action • Concentration of Enzyme and Substrate – With a fixed amount of enzyme and an excess of substrate molecules • the rate of reaction will increase to a point and then level off – Leveling off occurs because all of the enzyme is used up • Excess substrate has nothing to combine with – Add more enzyme reaction rate increases again Enzyme-Substrate Concentration Nucleic Acids • Nucleic Acids: found in the chromosomes in every nucleus of all cells. DNA: contains the genetic code of instructions. found in the chromosomes of the nucleus Consists of 3 parts called a nucleotide: 1. phosphate 2. sugar 3. nitrogen base – RNA: directs protein synthesis • found in nucleus, ribosomes & cytoplasm.