The nitrogenous bases of dna are held together by

Enzymes are proteins that speed up reactions by providing an additional energy source supplying additional molecules for the reaction removing inhibitors that slow down reactions lowering the amount of energy required

Me with these questions if you’re it sure don’t answer

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.