5) Using FRAP (Fluorescence Recovery After Photobleaching), you can measure the diffusion rate of membrane proteins. You attach a fluorescent marker to your protein of interest, bleach a small region of the cell membrane with an intense laser light, and determine the time it takes for the bleached spot to recover fluorescent signal (see figure below). (a) (b) Bleach Laser bleaching of fluorescent marker Fluorescence intensity recovery Recovery Time How would the recovery time of your protein change if the membrane contained a higher concentration of unsaturated fatty acids? Why? How would the recovery time of your protein change if you conducted the experiment at a lower temperature? Why? How would the recovery time of your protein change if it were anchored to the membrane skeleton? Why?

5) Using FRAP (Fluorescence Recovery After Photobleaching), you can measure the diffusion rate of membrane proteins. You attach a fluorescent marker to your protein of interest, bleach a small region of the cell membrane with an intense laser light, and determine the time it takes for the bleached spot to recover fluorescent signal (see figure below). (a) (b) Bleach Laser bleaching of fluorescent marker Fluorescence intensity recovery Recovery Time How would the recovery time of your protein change if the membrane contained a higher concentration of unsaturated fatty acids? Why? How would the recovery time of your protein change if you conducted the experiment at a lower temperature? Why? How would the recovery time of your protein change if it were anchored to the membrane skeleton? Why?

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter4: Cell Structure

Section: Chapter Questions

Problem 27CTQ: In what situation(s) would a transmission electron microscope be ideal, and why?

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Similar questions

1. Determine the following for positive staining. (a) dye, (b) charge of the chromophore/colored ion, (c) charge of the target cellular structure, (d) applications/target cell structure 2.Determine the following for negative staining. (a) dye, (b) charge of the chromophore/colored ion, (c) charge of the target cellular structure, (d) applications/target cell structure
3 cell membrane samples: A, B, and C were fluorescently labeled and subsequently photobleached. The recovery of fluorescence is given on the FRAP curve: (see image attached) Rank the 3 cell membranes in terms of DECREASING fluidity and explain your ranking based on their FRAP curves, most probable appearance, and composition of the membranes. Draw the expected image of the surface of the 3 membranes BEFORE photobleaching and AFTER fluorescence recovery as viewed under a fluorescence microscope.
Eosin (an acidic dye, negatively charged) is used to stain cytoplasm (basic, negatively charged), and at the same time, Methylene blue (a basic dye, positively charged) can also be used to stain cytoplasm (basic, negatively charged). Why both acidic and basic dye can be used to stain cytoplasm? Why the negative charged Eosin can also bind to negative charged cytoplasm without repulsion?
Both of the regular intravenous solutions administeredin medicine, normal saline and lactated Ringer’ssolution, are isotonic. Why is this important?
In a monolayer of cultured epithelial cells, the cells may or may not have formed tight junctions. What experimental test could be used to determine it the cells have functional tight junction structures? Place a small dye (1 k Da in molecular weight) into the culture media of cells cultured on a glass coverslip and use live imaging to monitor whether the dye can penetrate into the O cytoplasm of the cells, as would be expected if the cells have functional tight junctions. Inject a cell with a small dye (<1 kDa in molecular weight) and use live cell imaging to track whether the dye moves into neighboring cells, as would be expected if the cells have functional O tight junctions.
a. You selectively label phospholipids with a fluorescent dye and perform the FRAP assay. You detect a single fluorescence molecule move 100 micrometre into the photobleached area in 2.5 seconds. What is the diffusivity constant for this phospholipid? b. Increasing the ratio of unsaturated to saturated phospholipids in a biological membrane increases membrane fluidity. Describe how the FRAP photobleaching and recovery curves would differ between membranes with 63% and 41% unsaturated phospholipids. c. Draw the FRAP photobleaching and recovery curves for your answer in b. d. What does the “immobile fraction” in a FRAP experiment suggest (see diagram)?
Hoechst 33342 is a membrane-permeant dye thatfluoresces when it binds to DNA. When a population ofcells is incubated briefly with Hoechst dye and then sortedin a flow cytometer, which measures the fluorescence ofeach cell, the cells display various levels of fluorescence asshown in Figure Q17–1.
3 cell membrane samples: A, B, and C were fluorescently labeled and subsequently photobleached. The recovery of fluorescence is given on the FRAP curve: (see image attached) Rank the 3 cell membranes in terms of DECREASING fluidity and explain your ranking based on: their FRAP curves; most probable appearance; and most probable composition of the membranes
Why do we use sucrose solution when we observe plant cells? What explanation please..
8) Indicate which of the five major types of membrane protein (adhesion, enzymatic, recognition, receptor, and transport) is most likely to be involved in each of the situations described below: a) An oncologist wants to study the cells from a certain tumour that has been surgically removed from a patient. However, she must first treat the tumour with a solution affects a membrane protein on the tumour cells. Because of the effect of the solution on the membrane protein, the tumour tissue falls apart into individual cells. Type of membrane protein: b) Farmer Jebediah wakes up in the morning and makes himself an extra-strong coffee. The caffeine in the coffee attaches to a protein in the plasma membrane of his neurons, inducing a signal transduction cascade and causing Farmer Jebediah to be more alert Type of membrane protein:
Detergents are synthetic soaplike substances that are used todisrupt membranes and extract membrane proteins. Explainhow this process works.
In this problem, you will design a filter system for a flow cytometer. The four fluorescent dyes are FITC,PE, PE-TR,and PE-Cy5. Their emisison spectra are provided below. Detectors are arranged as shown in thefigure below. The FITC signal is detected from Filter 1, the PE signal from Filter 2, the PE-TR signal fromFilter 3 and the PE-Cy 5 signal from Filter 4. Part 4.1Provide a rationale for the order in which the filters are arranged with respect to the unfiltered signal. Part 4.2You are given 9 candidates from which you have to choose 4 for the filters in the diagram above. Choose4 and justify your selection.# Filter type WavelengthA Long pass 650 nmB Short pass 530 nmC Long pass 490 nmD Band pass 550-590 nmE Long pass 560 nmF Short pass 640 nmG Long pass 620 nmH Band pass 620-640 nmI Short pass 590 nm