LECTURE 5 OBJECTIVES1. Understand how biological macromolecules are built (condensation or dehydration reactions) and broken down (hydrolysis)• condensation and dehydration: build macromolecules• molecules are broken down by hydrolysis3. Be able to recognize carbohydrates (sugars) from their structural formulas and that they contain a carbonyl group (either analdehyde or a ketone). Know what a monosaccharide, polysaccharide, and disaccharide are.• disaccharide: formed from two monosaccharides by dehydration reactions (condensation reactions) which are reactions thatresult in the loss of components that form water.• double sugars• polysaccharides: polymers of hundred to thousands of monosaccharide subunits joined by glycosidic bonds• storage (energy and carbon) roles and structural roles.• lots of sugar blocks• starch, glycogen and cellulose• monosaccharides: simplest carbohydrates• single sugars• molecular formula: x(CH2O)5. Know that monosaccharides can exist in either a linear or cyclic (ring) form. Carbohydrates contain one or more asymmetriccarbons and so can exist as enantiomers.• monosaccharides: linear or cyclical• carbs: 1+ carbons, so they are enantiomers7. Know that glucose is a 6 carbon monosaccharide, sucrose is a disaccharide composed of glucose and fructose• glucose = 6 carbon • monosacc.• sucrose = disacch. • glucose + fructose9. Know that glucose forms two important polysaccharides, starch (glycogen) and cellulose. Starch is used for energy storageand that cellulose is used in plants to build cell walls (structural role). Starch is composed of 1-4 linked glucoses withoccasional 1-6 linked side chains. Cellulose is composed of multiple chains 1-4 linked beta glucoses (a different glucoseenatiomer than found in starch) and the individual chains are hydrogen bounded together which makes cellulose highlyresistant to degradation (hydrolysis)• glucose = starch and cellulose• starch = energy storage• 1-4 linked glucoses• cellulose = plants• 1-4 linked beta chainsLECTURE 6 OBJECTIVES1. Know the general structures of the three types of lipids (Fats, Phospholipids, and Steroids) and beable to state what their main biological functions are.• Fats:• facilitates absorption of vitamins• constructed from glycerol and fatty acids• glycerol: three carbon alcohol with a hydroxyl group attached to each carbon • attached to the 3-carbon alcohol glycerol (triglycerides)• fatty acid: carboxyl group attached to a long carbon skeleton• one fatty acid is attached to each OH in glycerol • phospholipids:• metabolism and cell signaling • when added to water, they self assemble into a bilayer, the hydrophobic tail faces the inside• two fatty acids and a phosphate group are attached to glycerol • fatty acid tales are hydrophobic • steroids:• carbon skeleton and four fused rings• hormones and signaling molecules• cholesterol is a very important steroid• lipids with four fused rings3. Know the difference between a saturated fat and an unsaturated fat and know the effect of the degree of saturation on thetemperature at which lipids solidify• saturated fats:• three fatty acids that are completely saturated• tend to stack together and form solids (butter)• can clog arteries, cardiovascular disease• unsaturated fats: • one or more unsaturated fatty acid• prevalent in fish and animals• the inflexibility of double bonds prevent them from stacking• liquids at room temperature5. Understand that all lipids are hydrophobic but that phospholipids have a double character by having a charged polar headgroup and a long hydrophobic tail• all lipids = hydrophobic• phospholipids have a charged polar head group and phospholipid tail 7. Know that cell membranes are composed of phospholipid bilayers in which the hydrophobic tails of the phospholipid clustertogether on the inside of the bilayer and the hydrophilic heads (with the charged phosphate group) that project outward wherethey can interact with water.• cell membranes: composed of phospholipid bilayers • the hydrophobic tails cluster together and face the inside• the hydrophilic heads project outward and interact with water• the bilayer arrangement forms a barrier between the aqueous exterior and the aqueous interior of our cells.LECTURE 7 OBJECTIVES1. Know that proteins are polymers of amino acids, that each kind of protein has a unique amino acid composition (order in whichthe amino acids are strung together) that cells contain thousands of different kinds of proteins and that each protein has aspecific cellular function.• proteins: polymers of amino acids• each protein has a unique composition of amino acids• each protein has a specific cellular function• structural, storage, transport, hormonal, receptor, etc.3. Be able to draw the general structure of an amino acid, know that there are 20 different amino acids used to make proteins,and know five different categories of amino acids based on the chemical character of their R groups (side groups)• 20 different amino acids used to make proteins• 5 different amino acids based on the chemical character:• non-polar• polar but uncharged• charged• acidic• basic5. Understand how amino acids are linked together by peptide bonds to make polypeptides (carboxyl and amino groups arejoined together by dehydration into a CN bond)• peptide bonds: link the amino acids• carboxyl and amino groups are joined together by dehydration into a CN bond 7. Understand that a protein’s function depends on the amino acids it contains and its overall 3-Dshape.• overall shape results from the interactions between the R-groups• function depends on shape9. Know what the 4 levels of protein structure are (primary through quaternary).• primary• the sequence of amino acids in the chain• secondary• hydrogen bonding • regular, repeating bonding between the N and O components of peptide bonds• helix form• bonding between every 4th amino acid bond• helical shape• b pleated sheath• bonding is between different segments of the polypeptide that come to parallel each other• tertiary • hydrogen bonds• ionic bonds• disulfide bridges between cysteines• hydrophobic interactions • non-polar amino acids cluster in interior away from water• stabilized by interactions between R groups within a polypeptide• H bonding between polar but uncharged R groups• ionic bonds between
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