Biology paper 1 - Health & Disease

• What are the types of pathogens that cause infectious diseases?

  Viruses, bacteria, protists, and fungi
• How can diseases caused by pathogens be spread?

  By direct contact, water, or air
• What do bacteria produce that can damage tissues?

  Toxins
• How do viruses reproduce?

  Inside cells, causing cell damage
• What are the symptoms of measles?

  Fever and a red skin rash
• Why are children vaccinated against measles?

  To prevent serious illness and complications
• How is the measles virus spread?

  By inhalation of droplets
• What does HIV initially cause?

  A flu-like illness
• What happens if HIV is not controlled?

  It attacks the body's immune cells
• What is the late stage of HIV infection called?

  AIDS
• How is HIV spread?

  By sexual contact or body fluid exchange
• What is tobacco mosaic virus (TMV)?

  A plant pathogen affecting many species
• What symptom does TMV cause in plants?

  A mosaic pattern of discolouration
• How does TMV affect plant growth?

  It reduces photosynthesis
• How is salmonella food poisoning spread?

  By bacteria ingested in food
• What symptoms are caused by salmonella?

  Fever, cramps, vomiting, and diarrhoea
• How is gonorrhoea transmitted?

  By sexual contact
• What are the symptoms of gonorrhoea?

  Thick yellow or green discharge
• How can the spread of gonorrhoea be controlled?

  By antibiotics or barrier contraception
• What is rose black spot?

  A fungal disease affecting plants
• How does rose black spot affect leaves?

  Causes purple or black spots
• How is rose black spot spread?

  By water or wind
• How can rose black spot be treated?

  Using fungicides and removing affected leaves
• What causes malaria?

  Protists
• What is the life cycle of the malarial protist?

  Includes the mosquito
• What are the symptoms of malaria?

  Recurrent episodes of fever
• How is the spread of malaria controlled?

  By preventing mosquito breeding and using nets
• What are the non-specific defence systems of the human body?

  Skin, nose, trachea, and stomach
• What does the immune system do when a pathogen enters the body?

  It tries to destroy the pathogen
• How do white blood cells defend against pathogens?

  By phagocytosis, antibody, and antitoxin production
• How does vaccination prevent illness?

  By stimulating antibody production
• What is the purpose of immunising a large population?

  To reduce the spread of pathogens
• What do antibiotics do?

  They kill infective bacteria inside the body
• Why is antibiotic resistance a concern?

  It reduces the effectiveness of treatments
• Can antibiotics kill viral pathogens?

  No, they cannot
• What is the role of painkillers?

  To treat symptoms but not kill pathogens
• Why is it difficult to develop antiviral drugs?

  They may damage the body's tissues
• How were traditional drugs discovered?

  Extracted from plants and microorganisms
• What is digitalis used for?

  As a heart drug
• What is aspirin derived from?

  Willow