The graph below shows the percent mortality in populations of lab animals exposed to increasing concentrations of two different pathogens (agent 1 and agent 2). Which of the following is a true statement about the LD50?  

  Lily (who has lice) brings a comb to school for picture day. After Lily combs her hair, Leticia asks to borrow the comb. Leticia later is diagnosed with lice. In this example, the comb is a(n)  

  Which of the following is true about cyanobacteria?  

  Give an example of a situation where one of Koch’s postulates does not work.  Refer to one specific postulate and one specific infectious disease and explain how the postulate does not hold true for this particular infectious disease.  

  Human immunodeficiency virus (HIV) spreads directly from person to person via intimate contact. HIV exhibits  

  The difference between an emerging and a reemerging disease is that emerging diseases__________, and reemerging diseases__________.  

  During photosynthesis, ATP is produced via  

  Which of the following diseases is caused by a helminth?  

  A microbe that is multicellular and photosynthetic, and has cells 50 μm in size, would most likely be a(n)  

  Within three hours of attending the church carnival, Maya and her family are all vomiting uncontrollably. Which of the following organisms have they likely ingested?