2. Discuss What contributions to marine science did the voyage of the HMS Challenger from 1872–1876 yield?

There are multiple lines of evidence that provide support for common ancestry and evolution. write 3-4 paragraphs describing at least three of them in detail. provide at least one example for each line of evidence.

Imagine a self-reactive t cell that has not undergone clonal deletion in the thymus (that is to say, it has escaped central tolerance). if it encounters self antigen in the absence of an infection or inflammation, what will happen to this self-reactive t cell? (select two answers) (a) the t cell undergoes clonal expansion. (b) the t cell gains effector functions. (c) the t cell undergoes apoptosis. (d) the t cell becomes activated. (e) the t cell becomes anergic.

What does the number 18.9984 represent in the image?