bio lectures 1 and 2
|what makes something alive?||1. Living organisms take in energy and/or nutrients from the environment. |
2. Living organisms sense and respond to the environment in controlled ways.
3. Living organisms grow and reproduce.
4. Living organisms contain genetic material.
5. Living organisms demonstrate homeostasis: the ability to regulate the internal environment to keep it within certain limits.
6. Living organisms have the capacity to evolve.
|stereochemistry||the three dimensional shape of a molecule.|
|steroisomers||molecules with the same order of bonding but different spatial relationships among the atoms.|
|enantiomers||Stereoisomers that are mirror images of each other|
|stereospecificity||implies that if one enantiomer fits the other enantiomer will not fit. examples: enzyme/substrate, hormone/receptor, antibody/antigen|
|hydrocarbons||chains of carbon atoms covalently bonded together with two hydrogen atoms attached to each carbon.|
|fatty acids||hydrocarbons with a carboxyl group|
|triglycerides||3 fatty acid chains are covalently bonded to glycerol. rich energy source, found in butter, lard, oils, animal fat|
|carbohydrates||provide energy for living organisms; each carbon has one water; monosaccharides, disaccharides, polysaccharides|
|Monosaccharide||one sugar; at least two hydroxyl groups. a carbonyl group|
|Disaccharide||two monosaccharides covalently bound togeth|
|uses of disaccharides||Short term energy storage; Transport sugars from one group of cells to another group of cells.|
|glycosidic bond||formed when water is split out and the two sugars are linked together by oxygen|
|Polysaccharides||long chains of sugar molecules covalently bound together.|
|functions of polysaccharides: starch, glycogen, cellulose, chitin||energy storage in plants, energy storage in animals, structural support in plants, exoskeleton in arthropods|
|in starch, molecules of glucose are joined in||alpha-1,4 glycosidic linkages|
|Starches form ___ which allow them to ___ forming ___||helical shapes, pack together tightly, dense granules in cells|
|amylose||long, unbranched chain of D-glucose molecules connected by alpha-1,4 linkages.|
|amylopectin||is a long, unbranched chain of D-glucose molecules connected by alpha-1,4 linkages on the chain with alpha-1,6 linkages at the branch points every 24-30 residues|
|glycogen|| a branched polymer of D-glucose molecules.|
- The chains are alpha-1,4 linkages
- The branch points are alpha-1,6 linkages that occur every 8-12 residues.
|cellulose||an unbranched polymer of glucose; residues are linked by beta-1,4 glycosidic bonds|
|chitin||structural polysaccharide; beta-1,4 linkages|