| Defence mechanisms | - Specific
- Non-specific |
| Specific defence mechanisms | - Slower response
- Specific to each pathogen |
| The two specific defence mechanisms | - Cell-mediated responses involving T lymphocytes
- Humoral responses involving B lymphocytes |
| Non-specific defence mechanisms | - Immediate response
- Same for all pathogens
e.g phagocytosis + physical barrier |
| Lymphocytes | - Type of white blood cell
- Detects proteins + pathogens that are foreign
- Produces antibodies - takes a few days |
| Lymphocytes functions | Allows immune system to identify:
- Pathogens
- Non-self material, foreign cells
- Toxins produced by pathogens, make antitoxins
- Abnormal body cells, cancer |
| How lymphocytes work | - Lymphocyte antibodies cause pathogens to stick together
- Easier for phagocytes to engulf them
- Has its own specific receptor that is complementary to a specific antigen
- When encountering antigen it multiplies
- Creating large numbers of identical lymphocytes with that specific receptor |
