What is natural selection? a process that selects variations that help with survival and that spreads the variations to more offspring

a process through which nature selects an individual within a population for extinction

a process that causes all populations to gradually increase in size

a process that causes random variations to appear in the offspring of every generation

According to this food web which of the following would be considered primary consumers

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.

Which of the following is a true statements about viruses? viruses have no nucleus. viruses are alive. viruses have a cell membrane. all viruses are deadly.