AQA Biology GCSE Topic 3: Infection and Response

These flashcards cover essential concepts from the lecture on infection and response, focusing on pathogens, disease prevention, human defense mechanisms, and the importance of vaccinations and antibiotics.

What are pathogens?

Microorganisms that cause infectious disease, including viruses, bacteria, protists, and fungi.

How do viruses multiply?

They invade host cells, use the cell's biochemistry to replicate, causing the cell to burst and release copies into the bloodstream.

What is binary fission?

A process by which bacteria multiply quickly by dividing.

What are the symptoms of measles?

Fever and red skin rash, which can lead to pneumonia, encephalitis, and blindness.

How is HIV primarily spread?

Through sexual contact or the exchange of bodily fluids such as blood.

What is herd immunity?

Immunity that occurs when a large proportion of a population becomes immune to a disease, thus reducing its spread.

What is the role of the skin in the human defense system?

Acts as a physical barrier and produces antimicrobial secretions to kill pathogens.

What happens during phagocytosis?

White blood cells engulf and consume pathogens, destroying them.

What is the significance of vaccination?

Vaccination helps individuals become immune to diseases by exposing them to a harmless form of the pathogen.

What are antibiotics?

Medicines that kill bacterial pathogens without harming body cells.

What is the role of monoclonal antibodies in pregnancy tests?

They bind to the hCG hormone present in the urine of pregnant women, indicating pregnancy.

What is a common method of preventing malaria?

Using insecticide-coated nets to prevent mosquito bites.

What can be a result of antibiotic resistance?

Bacteria that were once killed by antibiotics can survive and multiply, leading to ineffective treatments.

How do plants defend themselves against pathogens?

Plants use physical barriers, antibacterial compounds, and mechanical adaptations like thorns and hairs to deter pathogens.

What is the role of hydrochloric acid in the stomach?

To kill pathogens found in food and drink.

What is the purpose of clinical trials in drug testing?

To test the safety and efficacy of new drugs on volunteers and patients.

What are the symptoms of gonorrhea?

Thick yellow or green discharge from the vagina or penis, and pain when urinating.

What is tobacco mosaic virus?

A viral disease affecting many plant species, causing leaf discoloration and reduced photosynthesis.

How can fungal diseases like rose black spot be prevented?

Using fungicides or removing affected leaves.

What does it mean when a person is immune to a disease?

They can produce specific antibodies quickly upon re-exposure to the same pathogen, preventing symptoms.

How can we limit the spread of communicable diseases?

By improving hygiene, reducing contact with infected individuals, and removing vectors.