energy, enzymes and membranes

energy, enzymes and membranes - Principles of Biology...

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Principles of Biology Energy, Membranes, and Enzymes Energy o Can be used or stored o Can be changed from one form to another Thermodynamics o The study of energy transformations o Laws Energy cannot be created or destroyed Energy transformations increase entropy, and some energy is lost as heat Energy cannot equal absolute zero. Chemical reactions o Endergonic- reactions absorb energy o Exergonic- reactions release energy o Cells carry out thousands of reactions, cellular metabolism is the sum of these reactions. This is fueled by ATP. Enzymes o Speed up the cells chemical reactions o For reactions to occur, chemicals must absorb some energy o Enzymes act as catalysts. o Have specific 3D structure that determines where reactions occur in a cell. Membranes o Provide structural order for metabolism. o Fluid mosaic with proteins and other molecules o Plasma membrane is selectively permeable, controlling the flow of substances in/out o Phospholipids form a bilayer, have a hydrophilic head and two hydrophobic tails
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This note was uploaded on 10/05/2011 for the course BIOL 1543 taught by Professor Roberts during the Spring '08 term at Arkansas.

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energy, enzymes and membranes - Principles of Biology...

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