AS! Which material represents continental crust?

Mention true or false : a) cholera is marked by acute diarrhea and no urination. b)mosquitoes are the source of dysentery germs.

Which of these substances does not protect against invaders in the nonspecific immune response? a. saliva b. mucus c. tears d. urine

In general, characteristics that an organism survive and reproduce become more common in a population over time. what mechanism of evolution cause this change?