Distinguish between active and passive immunity with an example.

Distinguish between active and passive immunity with an example.

• A. Passive immunity provided by antibodies from another source (e.g., maternal antibodies) and is short-term
• B. Active immunity produced by the body's own response and is long-lasting; passive immunity is provided by antibodies from another source and is short-term
• C. Both are identical in duration and mechanism
• D. Passive immunity is formed after natural infection

Answer: (B)

Active immunity arises when the body's own immune system encounters an antigen and mounts a response, generating specific antibodies and memory cells that stay in the body. This memory makes the protection long-lasting, often for years or a lifetime, because future exposures can trigger a faster and stronger response. A practical example is vaccination or recovering from an infection, which trains the immune system to recognize and fight that pathogen in the future. Passive immunity, in contrast, is when ready-made antibodies come from another person or animal and are transferred to someone else. It provides immediate protection but is short-lived because those borrowed antibodies are eventually broken down, and no immunological memory is formed. A common example is maternal antibodies passed from mother to fetus through the placenta (and via breast milk) or receiving antibody-containing preparations after exposure. So the best description emphasizes that active immunity is produced by the body's own response and is long-lasting, while passive immunity is provided by antibodies from another source and is short-term.

Active immunity arises when the body's own immune system encounters an antigen and mounts a response, generating specific antibodies and memory cells that stay in the body. This memory makes the protection long-lasting, often for years or a lifetime, because future exposures can trigger a faster and stronger response. A practical example is vaccination or recovering from an infection, which trains the immune system to recognize and fight that pathogen in the future.

Passive immunity, in contrast, is when ready-made antibodies come from another person or animal and are transferred to someone else. It provides immediate protection but is short-lived because those borrowed antibodies are eventually broken down, and no immunological memory is formed. A common example is maternal antibodies passed from mother to fetus through the placenta (and via breast milk) or receiving antibody-containing preparations after exposure.

So the best description emphasizes that active immunity is produced by the body's own response and is long-lasting, while passive immunity is provided by antibodies from another source and is short-term.