Infection And Response Flashcards
What are pathogens?
Microorganisms that cause disease.
Types:
1. Bacteria (e.g., Salmonella).
2. Viruses (e.g., HIV).
3. Fungi (e.g., Rose black spot).
4. Protists (e.g., Malaria).
How do pathogens spread?
- Air (e.g., flu, common cold).
- Water (e.g., cholera).
- Direct contact (e.g., athlete’s foot).
What are viral diseases?
- Measles: Spread by droplets, symptoms include fever and rash; can be fatal. Prevented by vaccination.
- HIV: Spread via body fluids, damages immune system; can lead to AIDS. Controlled by antiretroviral drugs.
- TMV (Tobacco Mosaic Virus): Affects plants, discolours leaves, reduces photosynthesis.
What are bacterial diseases?
- Salmonella: Spread by contaminated food; causes fever, cramps, vomiting. Prevented by proper food hygiene.
- Gonorrhoea: STD causing discharge and pain; treated with antibiotics and prevented by condoms.
What is Rose Black Spot?
A fungal disease causing black spots on leaves of roses. Reduces photosynthesis. Treated with fungicides and removing infected leaves.
What is Malaria?
A disease caused by a protist, spread by mosquito bites. Symptoms include fever and chills. Prevented with mosquito nets and antimalarial drugs.
What are the body’s defence systems?
- Skin: Barrier.
- Nose: Traps particles.
- Trachea/Bronchi: Mucus and cilia trap pathogens.
- Stomach: Acid kills pathogens.
How does the immune system fight pathogens?
- White blood cells:
• Phagocytosis: Engulf pathogens.
• Antibody production: Specific to pathogen antigens.
• Antitoxin production: Neutralises toxins.
What are vaccines and how do they work?
Vaccines contain inactive or dead pathogens. They stimulate white blood cells to produce antibodies, creating memory cells for future immunity.
How do antibiotics and painkillers differ?
• Antibiotics: Kill bacteria (e.g., penicillin); don’t work on viruses.
• Painkillers: Relieve symptoms but don’t kill pathogens.
What is antibiotic resistance?
When bacteria evolve to survive antibiotics due to overuse or misuse (e.g., MRSA).
How are new drugs developed?
- Preclinical testing: On cells, tissues, animals.
- Clinical trials: On humans for safety, dosage, and efficacy.
• Double-blind trials: Neither doctors nor patients know who gets the real drug/placebo.
- Clinical trials: On humans for safety, dosage, and efficacy.
What is a placebo?
A substance with no active ingredients, used in clinical trials to test effectiveness of a drug.
Name a source of medicine derived from plants/microorganisms.
• Aspirin: From willow.
• Penicillin: From mould (discovered by Alexander Fleming).
Name a source of medicine derived from plants/microorganisms.
• Aspirin: From willow.
• Penicillin: From mould (discovered by Alexander Fleming).
