![Page 1: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/1.jpg)
Unit 1 – The Chemistry of LifeUnit 1 – The Chemistry of Life
• Chapter 6~ An Introduction to Metabolism
![Page 2: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/2.jpg)
Metabolism/BioenergeticsMetabolism/Bioenergetics
• Metabolism: The totality of an organism’s chemical processes; managing the material and energy resources of the cell
• Catabolic pathways: degradative process such as cellular respiration; releases energy
• Anabolic pathways: building process such as protein synthesis; photosynthesis; consumes energy
![Page 3: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/3.jpg)
ThermodynamicsThermodynamics• Energy (E)~ capacity to do work; Kinetic energy~ energy of motion;
Potential energy~ stored energy• Thermodynamics~ study of E transformations• 1st Law: conservation of energy; E transferred/transformed, not
created/destroyed
• 2nd Law: transformations increase entropy (disorder, randomness)
• Combo: quantity of E is constant, quality is not
![Page 4: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/4.jpg)
Free energyFree energy
• Free energy: portion of system’s E that can perform work (at a constant T)
• Exergonic reaction: net release of free E to surroundings
• Endergonic reaction: absorbs free E from surroundings
![Page 5: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/5.jpg)
Why doesn’t metabolism reach Why doesn’t metabolism reach equilibrium?equilibrium?
![Page 6: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/6.jpg)
Energy Coupling & ATPEnergy Coupling & ATP
• E coupling: use of exergonic process to drive an endergonic one (ATP)
• Adenosine triphosphate
• ATP tail: high negative charge
• ATP hydrolysis: release of free E
• Phosphorylation (phosphorylated intermediate)~ enzymes
![Page 7: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/7.jpg)
It’s the old saying that in order to make It’s the old saying that in order to make money you first have to have money!money you first have to have money!
![Page 8: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/8.jpg)
EnzymesEnzymes
• Catalytic proteins: change the rate of reactions w/o being consumed
• Free E of activation (activation E): the E required to break bonds
• Substrate: enzyme reactant• Active site: pocket or groove
on enzyme that binds to substrate
• Induced fit model
![Page 9: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/9.jpg)
The catalytic cycle of an enzyme.The catalytic cycle of an enzyme.
![Page 10: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/10.jpg)
Effects on Enzyme ActivityEffects on Enzyme Activity
• Temperature• pH• Cofactors:
inorganic, nonprotein helpers; ex.: zinc, iron, copper
• Coenzymes: organic helpers; ex.: vitamins
![Page 11: Unit 1 – The Chemistry of Life Chapter 6~ An Introduction to Metabolism](https://reader035.vdocument.in/reader035/viewer/2022081514/56649ea05503460f94ba2dfb/html5/thumbnails/11.jpg)
Enzyme InhibitorsEnzyme Inhibitors
• Irreversible (covalent); reversible (weak bonds)
• Competitive: competes for active site (reversible); mimics the substrate
• Noncompetitive: bind to another part of enzyme (allosteric site) altering its conformation (shape); poisons, antibiotics