Explain how white blood cells protect the body against pathogens.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
White blood cells protect the body against pathogens by several mechanisms:
1. They can engulf and digest pathogens through phagocytosis.
2. They produce antibodies that recognise and bind to specific antigens on the pathogen.
3. The antibodies are highly specific, allowing targeted attack of the pathogen.
4. They also produce antitoxins that neutralise toxins released by pathogens.
1. They can engulf and digest pathogens through phagocytosis.
2. They produce antibodies that recognise and bind to specific antigens on the pathogen.
3. The antibodies are highly specific, allowing targeted attack of the pathogen.
4. They also produce antitoxins that neutralise toxins released by pathogens.
Examiner tips
- Use the word "protect" and link each mechanism to the overall defence function.
- Mention both phagocytosis and antibody production to cover all points.
- Show the specificity of antibodies to demonstrate understanding.
- Include antitoxins to complete the list of immune responses.
Common mistakes
- Confusing antibodies with antitoxins or omitting one of the mechanisms.
- Using vague terms like "fight" instead of specific processes such as phagocytosis.
- Failing to explain that antibodies bind to antigens on the pathogen.
Mark scheme (4 marks)
- White blood cells can engulf and digest pathogens (phagocytosis)
- White blood cells produce antibodies
- Antibodies are specific to the pathogen / bind to antigens on the pathogen
- White blood cells also produce antitoxins to neutralise toxins released by pathogens
Key terms in this question
Related
- All Eduqas GCSE Biology revision notes →
- How to answer a "Explain" question →
- Decode the mark scheme abbreviations →