Student’s Assignment:

1. Define bacterial mutation? How can a mutation occur?
    
2. Mutations arise spontaneously at low frequency. Why?
    
3. Define the following terms.
   
                 a.   Frameshift mutation
   
                 b.  Missense mutation
   
                 c.  Nonsense mutation.
    
4. Could a gradient-agar plate be used for any antibiotic? Explain?
    
5. Give examples for lethal mutations?
    
6. A student performing the Gradient plate technique poured the Streptomycin agar on the bottom layer and then overlayered with plain Nutrient agar. Did he/she can expect the successful isolation of mutants?
   
                 a.  If yes, what will be his/her observation? Explain.
   
                 b.  If No, what will be his/her observation? Explain.
    
7. A student performing the gradient plate technique for the isolation of Escherichia coli mutants added the antibiotic Amphotericin B. What will be his expected result? Explain why?
    
8. Define auxotrophic mutants?  Explain how the auxotrophic mutants are isolated?
    
9. A researcher plated mutagenized yeast cells on a master plate containing complete and allow them to grow. He then did a replica plating technique to transfer some yeast from each colony on the master plate to a plate containing minimal medium. Predict the results that he may obtain?