Innate vs Acquired & Active vs Passive Immunity — NEET Biology

Which of the following statements are NOT correct regarding immunity and immune components? S1: Active immunity is acquired when preformed antibodies or antitoxins are directly injected into the body for rapid protection against foreign agents. S2: The cell-mediated immune response (CMI) is primarily mediated by T-lymphocytes, which do not secrete antibodies but help B cells in their production. S3: IgA antibodies are abundantly found in colostrum and mucosal surfaces, contributing to innate immunity by physically trapping microbes. S4: The exaggerated immune response to certain antigens, termed allergy, involves IgE antibodies binding to mast cells and leading to the release of chemicals like histamine. S5: Immunisation via vaccines is based on the memory property of the immune system, generating memory B and T-cells for intensified secondary responses.