Master the A Level Biology Exam. Use flashcards and multiple choice questions with hints and explanations to ace your test. Start your journey to excellence!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.


What is passive immunity?

  1. Immunity through natural infection

  2. Immunity achieved through vaccination

  3. Immunity gained through the transfer of antibodies

  4. Immunity developed from exposure to pathogens

The correct answer is: Immunity gained through the transfer of antibodies

Passive immunity refers to the short-term immune protection that is conferred through the transfer of antibodies from one individual to another. This can occur naturally, such as when maternal antibodies are passed to a baby through the placenta during pregnancy or through breast milk during breastfeeding. It can also be achieved artificially, for example, through the administration of antibody-rich serum or immunoglobulin preparations for immediate, short-term protection against specific infections. While natural infection and vaccination result in active immunity—where the body is exposed to a pathogen or a vaccine and produces its own antibodies—passive immunity does not involve the host's immune system generating a response; rather, it temporarily acquires the ability to fight off infections through antibodies that were produced by another organism. Therefore, option C captures the essence of what passive immunity entails by emphasizing the transfer of pre-formed antibodies rather than the body's own active response to infections.