Coalition Chemistry 1. a) Bulk movement is the overall movement of a fluid. Themolecules all move in the same direction. Diffusion however is the randommovement of molecules which usually results in a fairly even distribution. Inother words the movement is not guaranteed to move in one direction but theprobability that it will move in the lower gradient is greater.
Osmosis issimilar to diffusion but is differentiated by the membrane’s behavior. The cellmembrane does allow water to move from higher to lower concentrations but doesnot allow solutes do that. b) Water potential is the capacity of water to moveto a from a region where there is high water potential to low water potential. This action happens without the affect of outside forces. When outside actionsdue occur and they give water a high potential energy than the water will moveto the region where less potential energy is. Hydrostatic pressure is thepressure required to stop water the movement of water.Order now
This is a method ofmeasurement. The osmotic potential is the measure of tendency of water to movethrough a membrane which contains a solution. This occurs when a cell does notallow a hypertonic solution to leave the cell membrane. The cell begins toincrease with water but the cell membrane can not release the solution and thusthe water potential within the cell increases.
This causes the water to nolonger enter the cell. c) Hypotonic is less solute to a certain amount of water. Hypertonic is more solute to a certain amount of water. Isotonic is the equalamount of solutes in two different solutions.
d) Endocytosis is the inward bulgecauses by incoming molecules. Exocytosis is the expelling of a material outsidea cell. e) Phagocytosis is the process where the cell obtains solid matter. Thisis different from the pinocytosis where the cell obtains liquid matter. Theseboth are endocytic processes.
Receptor-mediated endocytosis is the process wherethere are interactions between a material and receptor sites on the cell. Inthis process the cell accepts the material if it matches with the receptorsites. f) Coated pits are areas which peripheral proteins indent the membrane. This is where the vesicles for certain materials are formed. The vesicle whichis formed is called the coated vesicle. g) Plasmodesmata are the links whichhold two adjacent cells together.
Gap junctions are the channels which allowmaterials to flow between cells. 2. The concentration gradient is the differencein the density of a material from one region to another region. Theconcentration gradient affects diffusion by allowing the substance to flow fromhigh concentration to low concentration. The concentration gradient affectsosmosis by the same manner it does in diffusion. The cell does not allow thesolution to exit the cell when water is entering.
This keeps the solution in thecell making the concentration high and thus no further penetration of water. 4. Diffusion is more rapid in gases because they are less dense than liquids. Theyrepel each other more resulting in faster diffusion. Diffusion is greater athigher temperatures because of the greater kinetic energy among the molecules. They push each other more making them less dense.
5. The concentration of thesolute is 1%. This happens because a 1% sugar solution is isotonic with that ofthe 1% sugar solution in the tubes. The 2% sugar solution was increased becausethe substance was hypertonic.
The membrane did not allow the hypertonic solutionto exit because the pressure from the hypotonic solution was forcing water in. This later reached an equilibrium when the hypertonic solution was gaining waterpotential and the water stopped rising. The vice versa happened in the distilledwater solution.