3.1.4 & 5 Fungal & protist diseases

• Fungal disease: rose black spot AND protist disease: malaria
• Disease: Rose black spot

  Caused by: A fungus

  Symptoms :

  ● Purple / black spots on leaves

  ● Leaves often turn yellow & drop early

  ● Affects growth of plant as photosynthesis is reduced

  How is it spread?

  ● In the environment by water or wind

  How can spread be reduced or prevented?

  ● Fungicides (kill fungi)

  ● Removing and destroying affected leaves
• Disease:Malaria

  Caused by:A protist

  Symptoms:

  ● Recurrent episodes of fever and can be fatal

  How is it spread?

  ● Malarial protist has a life cycle that includes the mosquito, which is a vector

  ● Mosquito feeds on infected blood then bites a human

  How can spread be reduced or prevented?

  ● Prevent mosquitoes breeding eg. drain water holes → fewer to pass on pathogen

  ● Mosquito nets (or insect repellent) → to avoid being bitten
• why is this statement wrong?

  “Bug spray prevents spread of malaria.”

  This is not specific enough. Instead, use the term insect repellent.
• why is this statement wrong?

  “Malaria is a pathogen.”

  A pathogen is a microorganism that causes disease. Malaria is the disease and the pathogen that causes it is a type of protist
• why is this statement wrong?

  "Malaria is caused by mosquitoes.”

  Malaria is caused by a protist that is carried by mosquitoes, so mosquitoes act as vectors.
• Suggest reasons for the reduced number of deaths from malaria each year. (2)

  ● Improved health care / new treatments

  ● Changing behaviour to avoid being bitten (or give example)
• Explain why bushes infected with rose black spots show reduced growth. (3)

  ● Less chlorophyll so less photosynthesis

  ● So less glucose made

  ● So less proteins / lipids / cellulose made (for growth)