Immunity:
Defense against pathogens (bacteria, viruses, fungi).
Innate and acquired components.
Crucial for preventing infections and fighting diseases.
Interferons:
Signaling proteins during viral infections.
Alert neighboring cells.
Activate antiviral defenses.
Limit viral spread.
Cells of Acquired Immunity:
B cells produce antibodies.
T cells have various immune functions.
Specific and targeted defense.
Antibodies:
Produced by B cells.
Bind to antigens (foreign substances).
Neutralize and mark pathogens for destruction.
Essential in clearing infections.
Cell-Mediated Immunity:
Mediated by T cells.
Recognize and attack infected cells.
Produce cytokines.
Coordinate immune response.
Active vs. Passive Immunity:
Active: Immune response to antigen, long-lasting.
Passive: Transfer of pre-formed antibodies or cells, immediate but temporary.
Vaccination:
Preventive measure.
Introduce harmless antigens.
Stimulate immune system.
Forms memory for future protection.
Crucial for disease control and prevention.
