True about cytokines is -: (A) It is always a polypeptide, (B) It acts on protein targets, (C) It takes pa in intrinsic enzymatic reactions, (D) Chemotactic
Answer is A. 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