University of Minnesota, Morris - BIOLOGY 222 CH16 1)The most successful parasites are the ones that live in harmony with their hosts

University of Minnesota, Morris - BIOLOGY 222

CH16

1)The most successful parasites are the ones that live in harmony with their hosts.        

2.         A human fetus has no resident microbial population.             

3.         Infection always leads to disease.        

4.          An infectious disease is an infection that impairs the normal state of health.

5.         Obligate intracellular parasites may be grown in special synthetic media.               

6.         During incubation and convalescence a person may still spread infectious organisms.        

7.         The infectious dose of most pathogens is about equal.           

8.         A strong attachment of a microorganism to a host cell automatically leads to disease.       

9.          High concentrations of some bacteria are necessary for successful invasion because only at high density are their virulence genes expressed.              

10.       Only Gram-positive bacteria produce exotoxins.