1. Give two methods you would use to determine if bacteria have flagella.
2. McConkey agar plates are used to isolate enteric bacteria. It contains bile salts and crystal violet which inhibits the growth of Gram (+) bacteria. The plate also contains lactose and a neutral red pH indicator in order to detect fermentation. Plates were grown at 37°C. (Note: if you choose to answer this question you must answer both part A and B)
A.) What component(s) make the media selective? What component(s) makes it differential?
B.) You inoculate the plate with E. coli, Serratia marcescens, and Staphylococcus epidermidis. E. coli and Serratia marcescens grew, but no growth occurred with the Staphylococcus epidermidis. The E. coli appeared pink in color instead of its usual white and the Serratia was white. What does this tell you about each bacteria?
3. You observe a bacterium with a spirochete morphology. What type of flagella does this microbe have? How do spirochete flagella differ from peritrichous flagella in location and how it moves the microbe?
4. List three structures of the Gram negative cell envelope and their function.
1. Give two methods you would use to determine if bacteria have flagella.
2. McConkey agar plates are used to isolate enteric bacteria. It contains bile salts and crystal violet which inhibits the growth of Gram (+) bacteria. The plate also contains lactose and a neutral red pH indicator in order to detect fermentation. Plates were grown at 37°C. (Note: if you choose to answer this question you must answer both part A and B)
A.) What component(s) make the media selective? What component(s) makes it differential?
B.) You inoculate the plate with E. coli, Serratia marcescens, and Staphylococcus epidermidis. E. coli and Serratia marcescens grew, but no growth occurred with the Staphylococcus epidermidis. The E. coli appeared pink in color instead of its usual white and the Serratia was white. What does this tell you about each bacteria?
3. You observe a bacterium with a spirochete morphology. What type of flagella does this microbe have? How do spirochete flagella differ from peritrichous flagella in location and how it moves the microbe?
4. List three structures of the Gram negative cell envelope and their function.
