Tutorial

In Griffith's experiments, he found that "smooth" strains of the bacteria Streptococcus pneumoniae could on occasion generate "rough" strains when grown in culture (in vitro). 

Q1: Would you expect rough strains to be able to produce smooth strains under these in vitro conditions?  Explain your reasoning.   

Q2: In Griffith's study, he found that dead smooth S. pneumoniae could transform living rough strains of S. pneumoniae when co-injected into a mouse (in vivo).    Would another species of dead bacteria give the same result? 

Q3: Would you expect that the ability of cells to take up extracellular DNA is regulate (and evolvable) trait, and if so what conditions would favor such a trait?  

07-Mar-2008 Close Window