BMSC 210 Midterm 1 Study Guide | 100% Correct Answers | Verified | Latest 2024 Version

BMSC 210 Midterm 1 Study Guide | 100% Correct Answers | Verified | Latest 2024 Version What are properties of all cells? - Growth Metabolism Evolution LUCA - Last universal common ancestor How do we decide how the phylogenetic tree is drawn? - Use ribosomes. All organisms have it and it has been the same for billions of years What are the domains? - Bacteria Archaea Eukarya What defines the domains of cells? - Their rRNA sequencing What domains are most closely related? - Archaea and eukarya What emerged from Archaea? - Eukarya How do we know kw when oxygen appeared in our biosphere? - Reduced iron deposits coating the bottom of ancient oceans Who invented microscopes? - Robert hooke What are Robert Koch's postulates on infectious disease? - 1. The microorganism or other pathogen must be present in all cases of the disease 2. The pathogen can be isolated from the disease Nederland host and grow in a pure culture 3. The pathogen from the pure culture must cause the disease when inoculated into a healthy, susceptible lab animal 4. The pathogen must be resonated from the new host and shown to be the same as the originally inoculated pathogen Why is staining important in microscopy? - Increases contrast Resolution - The ability to distinguish two adjacent objects as separate and distinct How is resolution determined? - Determined by the wavelength of light used and numerical aperture of lens. Shorter wavelength= better resolution. Higher numerical aperture = better resolution What is the limit of resolution for a light microscope? - 0.2 um What happens when we reach the limit of resolution? - Further magnification doesn't provide any additional detail Light microscopy - Uses visible light to illuminate cells Types of light microscopy - Bright field Phase contrast Dark field Flourescence Bright field microscopy - Specimens visible because of differences in contrast (density) between specimen and surroundings. Total magnification = objective lens magnification x ocular lens magnification Max mag is 2000x Why is oil used in microscopy? - Stops refraction Phase contrast microscopy - Phase ring amplifies