Answer:
In science, a variable is any item, factor, or condition that can be controlled or changed
Answer:
T and B cells.
Explanation:
Adaptive immunity is the kind of immunity that you acquire after exposure to an antigen (pathogen or vaccine), it involves memory in order to facilitate a quick response if there's a reinfection with the same pathogen.<em> T cells are responsible for the cell-mediated response while the B cells are responsible for the humoral response.</em> Both of these cells are specific to the pathogen's structure, therefore they can kill it directly.
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