Q1. What is the difference between a simple and differential stain?
Q2. What does a Gram stain detect? How does it differentiate bacterial cells? What color is a Gram-positive organism?
What color is a Gram-negative organism?
Q3. What are the principle differences between a gram - and gram + bacterial cell? (this is also covered in more detail in the external structures section)?
Q4. What do penicillin antibiotics act on with the bacterial cell?
Are gram + or gram - bacteria more susceptible to these antibiotics? Why don't they harm eukaryotes?
Q5. What does an acid-fast stain detect? How does it differentiate bacterial cells? What color are acid-fast organisms after staining with an acid-fast stain? Name an acid-fast organism.
Q6. Is a Schaeffer-Fulton stain a differential stain or a simple stain? What has to be done to the proteins in the cell membrane in order to drive the primary stain into the endospore?
Q7. What is an endospore? Why do bacteria make endospores?
What are their characteristics? What bacterial group discussed in class is medically important and form endospores? How does this relate to C. diff?
Q8. What does it mean for a bacterial growth medium to be selective? Differential?
Q9. Understand the selective and differential aspects of MacConkey's agar (MAC). What information does MAC provide about bacteria growing on this medium?
Q10. Understand the selective and differential aspects of
Mannitol Salt agar (MSA). What information does MSA provide about bacteria growing on this medium? What specific bacteria can be identified in this agar (how are they clinically important)?
Q11. What type of clinical samples is plated on Blood agar (BAP)? What broad type of bacteria are we looking for from a sample plated on BAP?