Comparisons between bacterial pathogens and related nonpathogenic strains have revealed
A)additional genes in the pathogen that are associated with virulence.
B)a reduced numbers of genes in the pathogen that force it to adopt a parasitic lifestyle.
C)additional genes in the pathogen that free it from a parasitic lifestyle.
D)loss of genes in the pathogen that normally allow detection by the host's immune system.

Question

Quizplus · Accepted Answer

Comparisons between bacterial pathogens and nonpathogenic strains have shown that the pathogenic strains often have additional genes called virulence factors that contribute to their ability to cause disease. These virulence genes may encode for toxins or other proteins that help the pathogen evade the host's immune system or colonize specific tissues. Non-pathogenic strains, on the other hand, lack these virulence factors and may have a more limited set of genes.

Comparisons Between Bacterial Pathogens and Related Nonpathogenic Strains Have Revealed