The frog population in the amazon basin varied. every 500 years, there was a mutational change leading to speciation. in between, the population remained the same with no observable changes. what pattern of macroevolution determined this change?
a: gradualism
b: adaptive radiation
c: punctuated equilibrium

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.