01:119:115 Lecture Notes - Lecture 5: Scanning Electron Microscope, Nuclear Pore, Optical Microscope
4 Oct 2016
School
Department
Course
Professor
Document Summary
Ratio of the size of image seen in relation to its actual size: resolution. Making things stand out: staining, types of microscopes. Visible light from light source passes through: bends light causes magnification. Major problem gives not much info about internal structure. 2 types of microscopes: tem (transmission electron microscope) Problems: kills cells, alters structure, expensive, lots of preparation. Cells: cells smallest unit that can carry life"s function, cells can be 2 types of states: More complex: all cells have a common evolutionary ancestor. Modifications occurred throughout evolutionary history: fractionation. Fractionation = taking cells apart in order to separate major organelles (good way to study cell structure) Method: cell homogenized in a blender, centrifuged, supernatant poured off, centrifuge again, result = pellets with cell components. Cytoplasm: interior of cell, filled with cytosol. Cell o cells are small: limits to cell size: Creates a boundary that all substances have to cross in order to enter/exit.
