When the offspring of a pure-bred black guinea pig and a pure-bred white guinea pig were mated among themselves, there were 271 black and 89 white offspring in the F2 generation. This means that black hair color in guinea pigs is due to a . recessive allele
dominant allele
codominant allele
mutation

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.