Infection & Response (Section 1) Flashcards
What is a disease?
A disease is an illness or disorder of the body or mind that leads to poor health
What are communicable diseases caused by?
Pathogens which are transmissible (can be spread around)
True or False? Only animals can be affected by pathogens
False - animals and plants can be affected
What is an infectious disease?
A disease caused by a pathogen that passes from infected individuals to uninfected individuals
Name some examples of infectious diseases
• Cholera
• HIV
• Malaria
• Tuberculosis
What are non-infectious diseases?
Long-term diseases that are not caused by pathogens
What are some examples of non-infectious diseases?
• Lung Cancer
• Cardiovascular Disease
• Depression
• Cystic Fibrosis
What are the 4 microorganisms which are pathogens?
• Bacteria
• Viruses
• Fungi
• Protists
What does bacteria do in terms of pathogens?
Bacteria reproduces rapidly and produces toxins which damage tissues of the body
What does viruses do in terms of pathogens?
Viruses reproduce rapidly (like bacteria) within host cells causing cell damage
Name the types of ways that diseases are transmitted
• Direct contact
• Water
• Air
Controlling the spread of disease can be done through the following:
• Good hygiene
• Effective sanitation
• Waste disposal
What methods are there to prevent the spread of pathogens?
• Hygienic food preparation
• Personal hygiene
• Waste disposal
• Sanitation
• Vaccinations
• Destroying vectors
What are some examples of viruses?
• Common cold
• Flu
• COVID-19 (what’s that!)
What sub-cellular structures do viruses not have?
• Nuclei
• Organelles
• Cytoplasm
• No way to monitor change in their internal environment
How do viruses reproduce quickly?
They insert their genetic material into host cells and then they create new protein capsules to build new viral particles
What happens to the host cell when the viral copies have been made?
It may burst open and release the viral particles inside which can go on to infect other cells
What is measles?
Measles is a highly contagious viral infectious disease which is mostly seen in children (most children are vaccinated against it)
How does measles spread?
Measles spreads by the inhumation of droplets from coughs and sneezes
What are the main symptoms of measles?
• Fever
• Red skin rash
What are the potential effects of having measles?
• Blindness
• Brain damage
How is HIV/AIDS spread?
• Direct sexual contact
• Exchange of bodily fluids such as blood
• From mother to child in breast milk
What are the symptoms of HIV/AIDS?
Flu-like illness
What does HIV do?
It travels to the lymph nodes and attacks cells of the immune system. (It can stay hidden in the immune system for years until the immune system is very badly damaged to the point it cannot deal with other infections such as cancer)
What is Tobacco Mosaic Virus (TMV)?
TMV is a plant pathogen that affects around 150 species including tomato plants and cucumbers
What are the symptoms of TMV in plants?
• Distinctive mosaic pattern of discolouration on the leaves (this happens because the virus infects the chloroplasts)
• The plant will grow less than usual due to the lack of photosynthesis
How is TMV spread in plants?
• Plants in direct contact with an infected plant
• Virus can stay in the soil for about 50 years
