This deep dive covers Understanding Antigens within Adaptive Immunity and Antibodies for GCSE Biology. Specific immune responses, antibody production, lymphocytes, memory cells It is section 2 of 15 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Understanding Antigens
Antigens are foreign substances that can trigger an immune response. The term comes from "antibody generator" — literally, substances that generate antibodies.
Examples of antigens:
- Pathogens: Bacteria, viruses, fungi, parasites all carry antigens on their surfaces
- Toxins: Poisonous substances released by bacteria
- Abnormal cells: Cancer cells may display abnormal antigens
Each antigen has a unique molecular shape on the surface of the pathogen. White blood cells recognise this specific shape and mount a targeted response.
Practice questions for Adaptive Immunity and Antibodies
What are antigens?
Explain how lymphocytes produce antibodies to destroy a specific pathogen.
Quick recall flashcards
What is an antibody?
A protein produced by lymphocytes (white blood cells) that binds to a specific antigen.
Each antibody has a unique shape that fits one antigen only — like a lock and key.
What is an antigen?
A protein on the surface of a pathogen (or cell) that the immune system recognises as foreign.
Antigens trigger the body to produce antibodies.