Which of the following organelles is found in plant cells but not in animal cells?

a. cell membrane
b. cell wall
c. nucleus
d. mitochondria

This is a coral reef ecosystem. many biotic and abiotic factors affect the health of this ecosystem. which set correctly pairs a biotic factor and an abiotic factor?

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.

Analyze how the four requirements for life were identified by scientists