<prompt> True about cytokines is -It is always a polypeptideIt acts on protein targetsIt takes pa in intrinsic enzymatic reactionsChemotactic  <response>: They are a broad and loose category of small proteins 5-20 kDa that are impoant in cell signaling. They act on receptors Ref: Ananathanarayanan Panikers textbook of microbiology 9th edition pg: 152 