Which sphere is not a part of the cycling of oxygen through earths systems

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 does the color of light affect the germination time (amount time a plant takes to develop) of a radish seed?

Atest cross can be used to -predict the phenotypes of a monohybrid cross -predict an unknown genotype of a purebred dominant plant -cross-breed dominant and recessive plants -give probabilities that a trait will appear