Biochemistry To be used with Biochemistry Guided Notes Gaccione/Bakka

Organic vs. Inorganic Molecules OrganicInorganic Does not contain C, H, and O at same time (Example: H 2 0) Carbon is the key element— the element of life Water: makes up 60 to 98% of living things—necessary for chemical activities and transport Salts: help maintain water balance Example: Gatorade—electrolytes Carbon can bond with itself and form many times for bonds (single, double, triple and rings) 4 Organic Molecules: 1. Carbohydrates 2. Lipids 3.Proteins 4. Nucleic Acids Contains Carbon (C), Hydrogen (H), and Oxygen (O) (Example: C 6 H 12 O 6 ) 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 C 6 H 12 O 6 Have a single ring structure Example: Glucose Fructose

Disaccharides - means two sugars All have the formula C 12 H 22 O 11 Example: glucose + fructose = sucrose (table sugar)

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 MonosaccharidesDisaccharides Polysacchrides

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 –C 6 H 12 O 6 + C 6 H 12 O 6  C 12 H 22 O 11 + H 2 O 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 –C 12 H 22 O 11 + H 2 O  C 6 H 12 O 6 + C 6 H 12 O 6

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. Skin6. hemoglobin 3. Hair7. 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.