Vaccines function based on the concept of immunological memory.

Which career is usually the first person the patient interacts with in healthcare institutions?

Observe this life cycle of Trypansoma cruzi, the causative agent of Chagas disease. What is an appropriate term for its mode of transmission to humans?

In both the 2009 swine flu and 1918 flu pandemics, one or more RNA segments of the circulating influenza strains had its origins in a non-human animal.

Which of the following would be an adaptive benefit to an infectious pathogen of antigenic variation?

What part of this phylogenetic tree does the arrow point to?

Which of the following cell types specifically bind to virus-infected cells that present antigens with MHC class I molecules?

What is an appropriate definition of an evolutionary trade-off?

What is the basis of antigenic variation in Trypanosoma brucei (sleeping sickness agent)?

Consider this published phylogenetic tree of HIV-1 (Human Immunodeficiency Virus) strains M/A, M/B, N and O, and several SIVcpz strains (Simian Immunodeficiency Virus of chimpanzees). Don’t mind the colors. Which of the following is an accurate statement of relationships?