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Biochemistry. Organic Chemistry. All living things are mostly composed of 4 elements: H, O, N, C “honk” Compounds are broken down into 2 general categories: Inorganic Compounds : Do not contain carbon Organic compounds Contain significant amounts of carbon.
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Organic Chemistry • All living things are mostly composed of 4 elements: H, O, N, C “honk” • Compounds are broken down into 2 general categories: • Inorganic Compounds: • Do not contain carbon • Organic compounds • Contain significant amounts of carbon. • Often found with common "functional groups"
Carbon: The “Swiss Army Knife” of Chemistry. • Carbon is essential to life for several reasons: • It can form strong stable (usually non-polar) covalent bonds • It can form up to 4 chemical bonds • It can form multiple bonds
Organic Compounds • Organic Compounds often form Polymers • Long chains of smaller molecules (not atoms) called monomers, bind to form huge Macromolecules • 4 Types: Carbohydrates, Lipids, Proteins & Nucleic acids
Carbohydrates • Includes: Sugars, starches, cellulose & glycogen • Made of Carbon ( C ), Hydrogen ( H ), and Oxygen (O ) • Following ratio of elements CnH2nOn • Sugars: Provide immediate energy for cells • Simple sugars include Glucose & Fructose since these are made of only 1 Carbohydrate molecule they are known as Monosaccharides Glucose: A Monosaccharide
Dehydration Synthesis • Monosaccharides can be linked together through the process of Dehydration Synthesis • Water is removed from 2 monocaccharides - resulting in a covalent bond between the 2 molecules • Sucrose (table sugar) is made of 2 sugars linked together and these are called Disaccharides • Require some digestion to be used by cells
Hydrolysis • Dehydration synthesis is a reversible process Called Hydrolysis. • A water molecule is inserted where the monomers join. Breaking their bonds.
Polysaccharides • Starches are many monosaccharides linked together in a single chain. These are called Polysaccharides. • Plants use Starch for energy storage e.g. Potatoes • Two types of starches • Amylose - Long strait unbranched chains • Pectins - many linked short Amylose chains Starch
Cellulose • Cellulose is made of long polysaccharide chains • Plants use this for structure (e.g. Wood) - not very digestible • Due to the reverse orientation of the monosaccharide subunits, digestive enzymes cannot hydrolyze the bonds between them Cellulose
Glycogen • Glycogen is a moderately branched polysaccharide • Animals use this for short-term energy storage. • Mostly stored in the human liver until converted to fat Glycogen
Lipids • Lipids are macromolecules including Fats, Waxes and Oils. • Primary function is energy storage. • Energy is stored in C-H bonds. • More efficient in storing energy • Lipids are made of 2 parts • Glycerol - an alcohol - Serves as backbone of the molecule • 3 Fatty acids - Long hydrocarbon chains
Types of fats • Saturated fats have long chains with no double-bonds • Unsaturated fats have double bonds • Polyunsaturated fats have many double bonds • Each time a double bond is encountered, the molecule "Bends" slightly, resulting in a lower density of the lipid. This makes the molecule more likely to remain liquid at room or body temperatures.And thus, less likely to clog cardiac arteries.
Other Lipids • 4 Other types of biologically important Lipids • Phospholipids - Important for membrane structure • Steroids - eg. Cholesterol & testosterone. Provide membrane support / serve as hormones • Terpenes - serve as important components of pigments • Prostaglandins - appear to act like localized hormones to induce cellular/tissue responses
Proteins • Proteins are made of Amino Acids • There are 20 different amino acids. Each having a similar general structure - Differ only in their “R” groups
Peptide Bonds • Amino acids form proteins via dehydration synthesis forming peptide bonds • Two amino acids linked together are called dipeptides • More than 2 linked together are called polypeptides - polypeptides can be thousands of amino acids long
Protein Structure • Protein types include globular proteins which are usually enzymes and Fiberous proteins which usually serve for structure (eg. Hair) • Proteins Exhibit 4 “levels of structure.
Primary Structure • Primary Structure of a protein is it’s sequence of amino acids • Primary Structure dictates all further levels of protein structure
Secondary Structure • The Sequence (primary structure) causes parts of a protein molecule to fold into sheets or bend into helix shapes - this is a protein’s Secondary Structure.
Tertiary Structure • The protein then can compact and twist on itself to form a mass called it’s Tertiary Structure
Quaternary Structure • Several Proteins then can can combine and form a protein’s Quaternary Structure • Various conformations are usually caused by the formation of hydrogen or disulfide bonds. • PH, changes or heat can disrupt these bonds, permanently denaturing the protein.
Nucleic Acids • Two types of Nucleic acids • DNA (Deoxyribonucleic Acid) • RNA (Ribonucleic acid) • DNA is Formed of in a "Double Helix" - like a spiral staircase.
Nucleotides • DNA is formed from Nucleotides • These are made of 3 components • A 5-Carbon Sugar • A Nitrogenous base • A Phosphate group • Nucleotides form a backbone through linkages from the OH group of the 3rd carbon to a phosphate group of the adjoining nucleotide. These are called Phosphodiester bonds
Types of Nucleotides • For DNA There are 4 different Nucleotides categorized as either Purines (double ring) or Pyramidines(single ringed). These are usually represented by a letter. These Are: • Adenine (A) • Cytosine (C) • Guanine (G) • Thymine (T)
Base Pairing Rules • Each "Rung" of the DNA "staircase" is formed by the linking of 2 Nucleotides through Hydrogen Bonds. • These Hydrogen bonds form only between specific Nucleotides. This is known as Base Pairing. The rules are as follows: • Adenine (A) will ONLY bond to Thymine (T) • Cytosine (C) will ONLY bond to Guanine (G)
RNA • AKA ribonucleic acid • RNA differs from DNA in several important ways. • It is much smaller • It is single-stranded • It does NOT contain Thymine, but rather a new nucleotide called Uracil which will bind to Adenine.
ATP • Short for Adenosine Tri-Phosphate. ATP is closely related to nucleic acids. • Composed of Ribose, Adenine & a phosphate group • Phosphate group has ability to bind/release additional phosphate group allowing it to store or release energy