Table 6.

Assessment of student acquisition and retention of content knowledge

Question and evaluation of answer	Pretest	Posttest
What is a genomic island?a	n = 23	n = 14
No idea/no answer	57%	0%
Wrong	39%	14%
Partial credit	4%	50%
Correct	0%	36%
How does genetic information get into an island? How do you know how it got into an island?b
No idea/no answer	65%	14%
Wrong	13%	0%
Partial credit	22%	43%
Correct	0%	43%
Suppose you had a group of bacterial strains from different regions of the world that are all the same species, yet some are more virulent than others. If you sequenced the genomes of all these strains, what feature(s) would you look for in those genome sequences that might confer strain-to-strain variability in virulence among bacterial strains of the same species?c
No idea/no answer	48%	7%
Wrong	17%	0%
Partial credit	13%	14%
Acceptable	22%	36%
Good	0%	43%

^aFull credit was given for responses that included the concept of sequences or sets of genes unique to one strain within a bacterial species that may confer virulence. Partial credit responses lacked the possible link to virulence.

^bFull credit responses included both some mention of modes of horizontal gene transfer (e.g., phage transduction) and evidence, such as phage gene remnants and/or transposition-related sequences (transposases, insertion sequences). Partial credit responses typically failed to answer the second question.

^cGood answers described possible virulence factor functions (e.g., toxins, iron uptake, adhesins, etc.). Acceptable answers invoked differences in gene content without mentioning specific potential functions. Partial credit was given for “genomic islands.”