Air moves into the lungs because

A) the gas pressure in the lungs is less than outside pressure.
B) the volume of the lungs decreases with inspiration.
C) the thorax is muscular.
D) contraction of the diaphragm decreases the volume of the pleural cavity.
E) all of these.

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.