Apathogen is best described as a pathogen is best described as an organism that remains in the body for a short time. a source of microbial contamination. a microorganism that remains with the person throughout life. a microorganism that may cause a disease under certain circumstances. any microorganism that causes disease.

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.

How is the national wildlife refuge system similar to the pacific region coastal program? a. both programs are concerned with providing habitats for wildlife b. both programs are primarily concerned with preserving fish species c. both programs have set aside 150 million acres of land d. both programs are under the u. s. fish and wildlife service

The first generation of offspring from the cross of two parents is called the a. f1 generation b. f2 generation c. short generation d. p generation