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Details Title: Human Physiology Description: Chapter 4 - Enzymes and Energy Total Flash Cards: 14 Created: 09/11/2007 19:50:01	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term Enzymes Definition - in general, proteins "most enzymes are proteins" - biologic catalysts * increase reactions rate * unchanged by reaction * does not change reaction or product Term Enzymes: How do they work? Definition *Large molecules with specific 3-dimensional shape (conformation) - active sites or pockets *Substrates(reactants) shape that matches the active site ~lock and key model ~induced-fit model Term Types of Enzymes Definition *hydrolases-hydrolysis(add H2O to break apart) *phosphateses-removal of phosphate gp *synthases and synthetase-dehydration synthesis(remove H2O to combine) *dehydrogenases-remove hydrogen *kinases-add phosphate groups *isomerases-rearrange atoms to form structural isomers Term Types of Enzymes: Isoenzymes Definition -different version of the same enzyme ~same reaction ~different organ ~slightly different amino acid sequence Term Enzyme Activity: Influenced by (4) Definition *Temperature and pH *Concentration of cofactors and coenzymes *Concentration of enzymes and substrates *Stimulatery or Inhibitory effect of products Term Enzyme Activity: Temperature Definition inc temp=inc reaction up to a point just about 37* (body temp) and then plateus and then drops Term Enzyme Activity: pH Definition differen enzymes have different pH optimums Term Enzyme Activity: Cofactors Definition ex:Ca2+, Mg2+, Mn2+, Cu2+, Zn2+ - allows substrates to fit in active sites - participates in temporary bonds Term Bioenergetics: Entropy Definition -degree of disorganization is a system's total energy ~more disorganized=more entropy C6H12O6 = more organized, more free energy, more ability to do work Term Bioenergetics: Second Law of Thermodynamics Definition the amount of entropy increases in every energy transformation Term Bioenergetics: Free Energy Definition Energy in an organized state - as entropy increases, less energy is available for work Term Bioenergetics: Endergonic Reactions Definition high to low entropy -must input energy, consumes energy - products contain more free energy than reactants Term Bioenergetics: Exergonic Reactions Definition low to high entropy - release energy - products contain less free energy than reactants Term Bioenergetics: ATP Definition Adenosine Triphosphate - Universal Energy Carrier exergonic (burning glucose) endergonic (making ATP)