BIOLOGY 111 1st Edition Lecture 9 Outline of Last Lecture I. MicrotubulesII. MicrofilamentsIII. Intermediate FilamentsIV. Membrane Structure and FunctionOutline of Current Lecture I. Osmosis II. Tonicity III. OsmoregulationIV. MetabolismV. Gibbs Free Energy Current LectureOsmosis- The diffusion of free water across a selectively permeable membrane- Water moves from an area of low solute to an area of high solute- Water moves from an area of high concentration to an area of low concentrationTonicity – the ability of a solution to cause a cell to gain or lose water- Hypotonic solution- The solute concentration is lower outside of the cell than inside.- Water goes inside the cell - Turgid is very firm- Normal for plants- Hypertonic solution- The solute concentration is higher outside of the cell than inside. - Water rushes outside of the cell- Plasmolyzed – causes wilting These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Isotonic solution- The solution concentration is equal on inside and outside of cell- Flaccid means limp Osmoregulation – the control of water balance (necessary for adaption and survival) Passive Transport – moves substances with their concentrating gradient Active Transport – moves substances against their concentration gradient- Because it goes against, it requires work, which requires energy (in the form of ATP)- Electrogenic pumps – transport protein that generates a voltage across a membrane- Sodium-potassium pump – animal cells- Proton pump – plants, fungi, and bacteria*these two types of electrogenic pumps do the same thing, just differ in structure- Co-Transport uses energy from a favorable gradient to drive transport against an unfavorable gradient - These are extremely specific to their particle (glucose-H+ cotransporter will only carry glucose and Sucrose-H+ cotransporter will only carry sucrose)Phagocytosis – a cell engulfs a particle by wrapping itself around it and packaging it within a food vacuolePinocytosis – the cell gulps droplets of extracellular fluid into tiny vesicles.Receptor-mediated Endocytosis – enables the cell to acquire bulk quantities of specific substances by inward budding vesicles containing proteins with receptor sites specific to the molecules being taken in.Chapter 8Metabolism is the totality of an organism’s chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of an organism.- Catabolic pathways release energy by breaking down complex molecules into simpler- Anabolic pathways consume energy by building complex molecules from simpler onesEnergy is the capacity to cause change and types include potential, kinetic, chemical, and heat- Potential energy is more unstable while Kinetic energy is more stableThermodynamics is the science of energy transformations - 1st law of thermodynamics (conservation of energy) – energy cannot be created nor destroyed - 2nd law of thermodynamics every transformation of energy is accompanied by increase in entropy (disorder)- Every process in cell increases total entropy(disorder) making less energy available to do work in the future (it is a continuous process, never reaching equilibrium) - Eventually all usable forms of energy become heat (which cannot be converted to any other form of energy)- Spontaneous reactions occur without energy input- Spontaneous reactions increases total energy Gibbs Free Energy “G” refers to the amount of energy actually available to break and subsequently form other chemical bonds∆G = ∆H - T∆S- The change in free energy ∆G predicts whether the reaction is spontaneous or not - Only processes with negative ∆G are spontaneous- If the products of a reaction have less potential energy than the reactants, then the reaction releases energy and is exergonic and spontaneous.- If the products of a reaction have more potential energy than the reactants, then the reaction requires energy and is endergonic and not