cell structure methods of studying cells 3.1/3.2 0.0 / 5 ? BiologyCellular processes and structureA2/A-levelAQA Created by: Joseph FurnivalCreated on: 11-04-18 20:04 what is magnification The magnification is how many times bigger the image is when compared with the object 1 of 21 what is the equation for magnification size of image/ size of object 2 of 21 What is the resolution Is the minimum distance apart that two objects can be in order to appear as separate items 3 of 21 what is cell fractionation Its the process where cells are broken up and the different organelles they contain are separated out 4 of 21 In cell fractionation why are cells placed in a cold solution to reduce enzyme activity 5 of 21 why is the solution the same water potential as the tissues To prevent organelles bursting or shrinking as a result of osmosis 6 of 21 why is the solution buffered So the ph does not fluctuate and alter the structure of organelles 7 of 21 what is homogenation Cells are broken down by a homogeniser and it gives out organelles the fluid is called is a homogenate 8 of 21 what is ultracentrifugation This is where fragments are separated in a machine called a centrifuge 9 of 21 what are the steps of ultracentrifugation The tube filtrate is placed in a centrifuge and spun at low speeds,heavy organelles forced to bottom, fluid removed and transferred to another tube 10 of 21 what is this fluid called in ultracentrifugation the supernatant 11 of 21 true or false electron microscopes have a high resolving power true 12 of 21 true or false light microscopes have a good resolution false 13 of 21 true or false the electron microscope uses light to form an image false 14 of 21 what are the two types of electron microscopes Transmission and scanning 15 of 21 true or false for an a TEM a thin specimen should be used true 16 of 21 what happens high energy electrons are used on the specimen it could get destroyed 17 of 21 what are the main limitations of a TEM must be in a vacuum,a staining process is required, specimen must be thin,may contain artefacts 18 of 21 what are artefacts Are things that result from the way the specimen is prepared 19 of 21 True or false in an SEM a thin specimen is also used false 20 of 21 true or false the SEM has a lower resolving power than the TEM true 21 of 21
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