Presentation on theme: "Vocab review Monomer= generic name for a building block unit"— Presentation transcript:
1 Vocab reviewMonomer= generic name for a building block uniteg: a monosaccharide is a monomer of a polysaccharidePolymer= generic name for 3 or more monomers bonded togethereg= three or more monosaccharides bonded together are a polymer, specifically a polysaccharideDehydration synthesis= building bigger molecules by taking water outDegradation hydrolysis= breaking up big molecules into smaller ones by putting water in
2 long term energy storage Lipidslong term energy storageconcentrated energy
3 Lipids Lipids are composed of C, H, O 3 Classes: Do not form polymers Defining characteristic: long hydrocarbon chains (H-C) or rings3 Classes:fatsphospholipidssteroidsDo not form polymersbig molecules made of smaller subunitsnot a continuing chainMade of same elements as carbohydrates but very different structure/ proportions & therefore very different biological properties
4 Fats (triglycerides and fatty acids) Structure:glycerol3 fatty acidsenzymeLook at structure… What makes them hydrophobic?Note functional group = carboxylH2Odehydration synthesis
5 Fats have functions! Long HC chain Function: polar or non-polar? hydrophilic or hydrophobic?Function:energy storagecushion organsinsulates bodythink whale blubber!What happens when you add oil to waterWhy is there a lot of energy stored in fats?• big molecule• lots of bonds of stored energySo why are we attracted to eating fat?Think about our ancestors on the Serengeti Plain & during the Ice Age. Was eating fat an advantage?
6 Saturated fats All C bonded to H No C=C double bonds long, straight chainmost animal fatssolid at room temp.Mostly animal fats
7 Unsaturated fats C=C double bonds in the fatty acids plant & fish fats vegetable oilsliquid at room temperaturethe kinks made by double bonded C prevent the molecules from packing tightly togetherMostly plant lipidsThink about “natural” peanut butter:Lots of unsaturated fats Oil separates outCompanies want to make their product easier to use:Stop the oil from separating Keep oil solid at room temp.Hydrogenate it = chemically alter to saturate itAffect nutrition?
11 Phospholipids in water Hydrophilic heads “attract” to H2OHydrophobic tails “hide” from H2Ocan self-assemble into “bubbles” or bilayerswaterbilayerwater
12 Why is this important? Phospholipids create a barrier in water define outside vs. insidethey make cell membranes!
13 Steroids Structure: 4 fused C rings + functional groups + HC tail different steroids created by attaching different functional groups to ringsdifferent structure creates different functioncholesterol
14 Cholesterol Important cell component animal cell membranes precursor of all other steroidsincluding vertebrate sex hormones
15 Cholesterol helps keep cell membranes fluid & flexible Important component of cell membranehelps keep cell membranes fluid & flexible