Will mark! what is the first step in the life cycle of a plant that reproduces sexually? a. a new plant develops b. a seed is produced. c. the seed falls to the ground and germinates. d. a sperm cell fertilizes an egg cell.

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.