Micro 20

Midterm 1: study guide

Define:



Colony
Contaminant



Simple stain (direct and negative)

Answer:
 Where do you dispose of the different types of waste in the lab?
 What are the parts of the microscope and what are they for?
 How does the oil immersion lens increase resolution?
 What are the main ingredients of nutrient agar and what is the purpose of each?
 What are the limitations of using petri plates for determining abundance and diversity of environmental samples?
 What form of media is best for isolating bacteria? (broth, plate, slant?)
 What are the steps of aseptic transfer of cultures?
 What are the steps of smear preparation? What is the importance of heat fixing?
 What is the difference between a basic and acidic stain (charge and what they stain)?
 What are the steps of the gram stain, what does each reagent do (ex: crystal violet is the primary stain), and what do gram positive and negative cells look like after each step?
 Can you identify gram positive and negative cells on a slide, with shape and arrangement?
 What are common reasons why you may get an incorrect result with the gram stain?
 What are the steps of the acid fast stain, what does each reagent do (ex: carbol fuchsin/phenol is the primary stain and mordant), and what color are acid fast and non-acid fast cells after the acid fast stain procedure? What makes a cell acid fast?
 Can you identify samples with endospores, capsules, and