Enters the atmosphere through respiration and the burning of fossil fuels.
a. nitrogen
b. carbon dioxide
c. oxygen

Drag each tile to the correct box. arrange the layers and faults from oldest to youngest.

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.

Do plant cells perform cellular respiration?