affect of alcohol concentration on the leakgage of pigment throygh betroot plasma membanres Flashcards
What does beetroot contain?
= pigment betalin- purple
= vacuoles of plant cell walls
= cannot cross plasma membrnaes
= unless damaged
What do we do first?
= identity the absorbance of light througyh samples using a calorimeter using known concentrations to extract a calibration curve
= use the calibration curve to identify the ubknown concenration of belatin released from the bettrot discs after being soaked in different concentratons of alcohols
What is the methid?
= create a dilution series
= differenr concentrations of extract/alcohols
= 5cm^3 of total volume
= volume of water + volume of beetroot extract
= label 0-10
= the higher concentration the more purple pigment
what is qualitative?
= observations of colour
What is quantitative?
= colirimeter and absorbance compare
= place concentration of extract into colrimeter and plot a calibaion curve, percentage extract and absorbance
Why do we set up a water batt?
= set up a controlled temperature, water bath, 30 degrees, as temperature affects permeability of membranes
= higher could damage the proteins in the plasma membrane (intrinisc proteins)
Why do we put a bung on top?
= [revent evaporation, if it occured could alte the concentration in test tube
Why do we place 2 beetroot discs into each test tube?
= make sure we have the same surface area and same potential maximum betalin that culd move out
Why do we blot the water?
= remove excess water, remove any betalin released from curring bettroot
Why do we shake it?
= make sure the mixing with the alcohol and encourage releae of betalin from vacuole
What do we do with the results?
= compare with calibration curve and place the solutions with different concentration of ethanol and absorbance with colourimeter
Why would a higher temperature release the pigment?
= cause the membrane proteins to denature, so the pigment is released
Why may an alcohol influence the results?
= lipids are soluable in alcohol so alcohol will dissolve the phospholipi bilayer, and acid would cause the membranr proteins to denature and pigment released
