Energy Energy (E)– the ability to perform work Potential E (EP)- stored energy Kinetic E (EK)– energy of motion Heat – kinetic energy of molecules ----- Meeting Notes (11/15/12 14:43) -----
Endergonic Reactions Endergonic – energy inside Reactions that take in energy and store it in chemical bonds Photosynthesis
Exergonic Reactions Exergonic – Energy outside Reactions that release stored chemical energy Cellular Respiration
Energy of Activation EA – the amount of energy required to start the reaction Lit fuse on a firecracker Spark in an engine
Enzymes : Protein Catalysts Enzymes – proteins that speed up chemical reactions, each enzyme promotes a specific reaction Substrate – the molecule that is targeted by the enzyme
Enzyme : Substrate Sucrase : sucrose Lactase : lactose Helicase : DNA helix
Competitive inhibition – the inhibitor blocks the active site, preventing the enzyme from accepting any substrate molecules
Noncompetitive inhibition – the inhibitor changes the shape of the active site, preventing the enzyme from accepting any substrate molecules
----- Meeting Notes (11/15/12 14:43) ----- Picture of a Phospholipid
----- Meeting Notes (11/15/12 14:43) ----- Phospholipids form this structure in a aqueos solution
----- Meeting Notes (11/15/12 14:43) ----- Plasma membrane of an animal cell (pp80) Proteins allow for movement in and out of the cell
----- Meeting Notes (11/15/12 14:43) ----- Mosaic function: pp 80-81
Diffusion Diffusion- the natural tendency of molecules to move from areas of high to low concentration
Passive transport Transport that doesn’t use cellular energy
Osmosis : The diffusion of Water Osmosis occurs when the solute is not able to move across the membrane. In order to reach equilibrium, water moves across the membrane. Water concentration, not solute concentration determines direction of movement.
Hyper-, Hypo-, or Isotonic The concentration of solutes in a solution are compared with those inside the cell. Hypertonic – a solution whose concentration of solutes is higher than that in the cell Hypotonic- a solution whose solute concentration is lower than that in the cell Isotonic – a solution whose concentration os solutes is equal to that in the cell
----- Meeting Notes (11/15/12 14:43) ----- Transport proteins facilitate diffusion across membranes (pp 83)
Active Transport Active transport requires energy to move a substance through a cell membrane.
Exocytosis – “Outside the cell” bulk movement of materials out of the cell
Endocytosis – “Inside the cell” bulk movement of materials into the cell
Phagocytosis, Pinocytosis, Receptor-mediated endocytosis #33(phagocytose 1)
----- Meeting Notes (11/15/12 14:43) ----- Nrg flow and chemical recycling (pp 86)