Communicable Diseases

• What are communicable diseases caused by?

  Pathogens
• How do non-communicable diseases differ from communicable diseases?

  They cannot be transmitted between organisms
• What factors can affect health besides diseases?

  Diet, stress, and life situations
• How can health problems interact?

  They can worsen each other
• What makes HIV/AIDS particularly dangerous?

  It makes you vulnerable to other diseases
• What types of pathogens can cause diseases?

  Bacteria, fungi, viruses, or protists
• How do pathogens cause communicable diseases?

  Directly or through toxins they produce
• What are bacteria?

  Single-celled organisms
• How much bacteria is typically found in the human gut?

  Between 1 and 2 kg
• What is the size comparison between bacteria and viruses?

  Viruses are smaller than bacteria
• How do bacteria reproduce?

  By splitting in two (binary fission)
• What do viruses do once inside the body?

  They take over body cells and reproduce
• What are common symptoms of diseases?

  High temperature, headaches, and rashes
• How are pathogens spread through the air?

  By tiny droplets expelled when coughing or sneezing
• How can diseases be spread by direct contact?

  Through sexual contact, cuts, or needle punctures
• How can pathogens enter the body through water?

  By eating raw food or drinking contaminated water
• What is needed to grow bacteria in a lab?

  A liquid gel providing nutrients
• What does the culture medium provide for bacteria?

  Carbs for energy and nitrogen for proteins
• What factors affect bacterial growth?

  Temperature, nutrients, oxygen levels, and pH
• How do you calculate the number of bacteria at the end of the growth period?

  $\text{Bacteria at end} =$$\text{Bacteria at start} \times 2^{\text{number of divisions}}$
• What is one way to prevent bacterial growth?

  Raising or lowering the temperature
• Who was Gina’s Semmelweis?

  A doctor who promoted handwashing
• What did Semmelweis notice about childbirth deaths?

  Women delivered by doctors were more likely to die
• What did Louis Pasteur discover?

  Microorganisms caused disease
• What are key ways to prevent the spread of diseases?

  Hygiene, isolation, destroying vectors, vaccination
• What are the main symptoms of measles?

  Fever and skin rash
• How is measles spread?

  By air and is highly contagious
• What are the initial symptoms of HIV?

  Mild flu-like symptoms
• How does HIV affect the immune system?

  It attacks the immune system
• What is TMV?

  A plant pathogen affecting 150 species
• How does TMV affect plants?

  Causes discolouration and reduces photosynthesis
• What is Salmonella?

  Bacteria causing food poisoning
• What are the symptoms of Salmonella food poisoning?

  Fever, cramps, vomiting, and diarrhoea
• How is Gonorrhoea spread?

  By unprotected intercourse
• What are the early symptoms of Gonorrhoea?

  Thick yellow discharge and pain on urination
• What does Rose black spot cause in plants?

  Purple or black spots on leaves
• How is malaria transmitted?

  By mosquitoes acting as vectors
• What are the symptoms of malaria?

  Fever and shaking
• What is the first line of defense against pathogens?

  Skin acts as a physical barrier
• How does the skin protect against pathogens?

  By producing antimicrobial secretions