Acquired immunity involves both a humoral immune response and a cell-mediated immune response.

Sort the items into the appropriate bins depending on whether they are involved in the humoral response, the cell-mediated response, or both the humoral and the cell-mediated responses.

1. Helper T cells and cytokines
2. antibodies
3. B cells
4. antigen-presenting cells
5. plasma cells
6. cytotoxic T cells
7. memory cells

Which of the following statements most accurately describes convergent evolution? the process in which two similar species evolve separately from each other and share similar characteristics the process in which a single species evolves into two or more new species the process in which two entirely different species evolve in response to each other the process in which two different species evolve separately from each other but still share similar characteristics

20 the main source of energy for our planet comes from the

How are fossils used to date organisms?