| 1. | Active immunity involves antibodies produced by another organism, while passive immunity involves self-produced antibodies. |
| 2. | Active immunity is immediate, whereas passive immunity requires a period of time to develop. |
| 3. | Active immunity results from the introduction of antigens into the body, leading to antibody production, while passive immunity involves the direct transfer of antibodies from one individual to another. |
| 4. | Active immunity lasts for a short period, while passive immunity lasts for a lifetime. |