This discussion gives you the opportunity to demonstrate your understanding of microscopy in general and, more specifically, the different types of microscopes used to study microorganisms in terms of their attributes and limitations. You'll also demonstrate your understanding of the different staining procedures discussed in Chapter 3 in terms of how they may be applied in the identification of microorganisms.

Using the information you learned from your readings and the videos you viewed for this module, compose answers to the following problems and post them on the discussion forum. Please respond thoughtfully and in your own words, supporting each statement of fact with cited sources. Your response to each problem should be at least 125 words.

1.What are the advantages and disadvantages of the different types of light and electron microscopes discussed in Chapter 3 that are used to study microorganisms? Focus your response in terms of the following parameters:

?Range of magnification
?Resolving ability
?Sample preparation
?Possible states of sample (e.g. whole organism, part of, living, non-living, etc.)

2.What type of microscope would you use to investigate each of the following scenarios and why (your answer to problem 1 will help):
?Determine the relative sizes of two eukaryotic cells.
?Determine how many bacteria are dying after a chemical treatment.
?Determine where in a eukaryotic cell a particular protein is localized.
?Identify a virus from a contaminated sample.
?Visualize the sensory hairs on the surface of an ant's antennae.

3.What are advantages and disadvantages of the differential staining techniques discussed in Chapter 3 that are used to study microorganisms? Focus your response in terms of the following parameters:
?Ease and cost of sample preparation
?Why you would use it (i.e. what information is imparted)
?Specificity of identification
?Chance of false positives or negatives