why do new species evolve more rapidly after a mass extinction? a. few organisms survive, which allows the remaining organisms to reproduce rapidly. b. mutations increase during mass extinctions, which then increase the rate of evolution. c. ecological niches become available for organisms to evolve into by adaptive radiation. d. there is a lot more food available, so the remaining organisms are able to flourish.

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

All vaccination should(n’t) be mandatory! 1.at least 5 sentences explaining 2.why? 3.in the end summarize the sentence

Which of these is a provisioning service people get from the ocean