Exam 2 Review Kayotype Analysis Spectral karyotyping rainbow of chromosomes Determines if there is a translocation o Part of one chrom detaches and attaches onto another Chronic Myeloid Leukemia Nowell and Hungerford density of cells much smaller lethal and progressive disorder increase in number of leukocytes not alarming unless persists for a few months increase for 5 years without intervention then WBC are so high and organs are destroyed secondary disoder ex kidney failure because too many cells and proteins are released taking up too much space for other cells early detection through Bone Marrow biopsy o cells taken caused to proliferate view under microscope if chromosome 22 is shortened and reciprocal translocation with 9 and 22 indicates CML BCR from 22 attaches to ABL on 9 o when BCR and ABL come together gene is always on o amino NH3 BCR ABL COO carboxylic o kinase indicates cells to proliferate o Transcribed translated into protein tells cells to proliferate cancer Hard to treat b c its genetic o Treated with drug that inhibits ABL and cell proliferation o Bone marrow Visualization of Chromosomes 1 Growing population of cells proliferation a Replicating after treated with MPF mitosis promoting factor i cyclin CDK1 ii staining pattern unique for chromosomes 2 Treated w colchicine for 12 20 hrs plant extract that inhibits microtubules what pulls chroms apart in metaphase 3 Accumulate cells in metaphase 4 Fix cells in Methanol acetic acid 5 Trympsin solution 10 15 min 6 Stain with Giemsa what codes for banding a pattern that allows alignment of chroms When looking under microscope many cells with many nuclei on slide chromosomes spread on surface cut chromosomes look at lengths staining to detect which chromosome Transport Passive Transport simple diffusion o equilibrium reached with time o concentration of molecule inside and out are equal facilitated diffusion carrier mediated o protein embedded in membrane that speeds up process Facilitated Diffusion a an aqueous channel or Extend across lipid bilayer Allow movements of specific molecules Ex glycerol porin o 6 helicies w 2 selectivity loops o Glycerol straight chain sugars urea glycine b c 4 things go through it competition b via a carrier o Has a polar pore and non polar exterior that interacts with membrane Aka transporters bind the specific solute Undergo conformational changes to transfer across membrane When transporter is saturated binding sites are occupied rate of transport Vmax is highest Each transporter has a characteristic affinity for its solute wont have random fatty acid trying to bind Km on concentration x axis concentration at highest rate Km Vmax Binding site can be blocked by inhibitors or glucose itself Ex glucose translocator protein o 12 alpha helicies o GLUT 1 2 3 4 5 o most tissues GLUT 1 and 3 Km 1mM glucose o most tissues getting glucose at 100 value of transport o muscles adipose GLUT 4 Km 5mM o liver pancreas GLUT 2 Km 15mM o GLUT1 helices form wall of cylinder hydrophobic pocket where ring structure of glucose is recognized What are the molecular features of the glucose transporter subunit in facilitated diffusion 12 alpha helicies with amino and carboxylic ends on cystolic side cytoplasm hydrophobic pocket conformationally similar for ring structure of glucose How would you determine whether the transport of the amino acid glycine into red blood cells occurs by simple diffusion or by facilitated diffusion If glycine were to be imported by facilitated diffusion how could you determine whether or not another amino acid such as methionine moves into the cells by the same carrier Simple diffusion linear continuously flows in at constant speed Facilitated diffusion shows leveling off of glycine doesn t continuously flow in Mix glycine and methionine together they start diffusing through membrane o but if they are using the same carrier they are competing to diffuse and the rate of diffusion would be slower showing facilitated o if they are moving in at the same rate they are using simple diffusion because there is no competition Channel glycerol uptake in E coli aqueous channel for specific mol cell wall and plasma membrane arediffusive barrier Why might a single mutation in E coli result in simultaneous altered movements of glycerol a four carbon sugar and urea through the cell s membrane Glycerol porin transports glycerol straight chain sugars urea glycine Theyre using the same channel so if Ecoli has a mutation it s aqueous channel or porin is altered and the uptake of glycerol sugar and urea is effected Example mutations of gene coding for glycerol channel in mice makes mice obese because degradation of lipids involves movement of glycerol out of fat cells and if glycerol can t move mice become fat glycerol d manitol d sorbitol d ribitol all can pass through channel because geometry of channel o TEST mutating gene for glycerol channel and all molecules will be effected because none can pass through now o TEST competition add glycine and rate of glycerol will be slower b c of competition Aquaporin proteins embedded in the cell membrane that regulate the flow of water abundant in epithelial cells of kidney 6 alpha helices in green form wall of cylinder core provides channel with 2 selectivity loops in cytoplasm and extracellular which selects for the water 28 KD amino and carboxylic ends on cystolic sugar chain that goes out into extracellular space What is the mechanism responsible for the increased capacity of adipocytes to transport glucose from the blood in response to an elevation in the concentration of blood insulin Give the details Outline the study discussed in lecture that demonstrated the phenomenon using cultured adipocytes High blood glucose causes pancreas to secrete insulin cell signaling molecule causes fat cells adipocytes to take up more glucose releases GLUT4 receptors that fuse w membranes to bring in more glucose fluorescent tag on GLUT4 w insulin moved everything outwards to membrane o no insulin didn t move to cell membrane Active Transport ch 11 pg 656 Primary ATP broken down to function o electrogenic pump voltage in cell will be more negative voltage allows for more energy ATP o J Skou 1957 more negative insisde o Na K ATPase Structure Every cycle discovered Na K ATPase electrogenic pump establishes voltage gradientacross membrane discovered presence of ions had effect on ATPase ATP ADP Pi cytoplasm subunit 10 membrane spanning extracellular subunit 1 membrane
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