Overview
This lecture explains the key characteristics of fungi and protists, their role as pathogens, and examples of the diseases they can cause in plants and humans.
Characteristics of Fungi
- Fungi are eukaryotic organisms like plants and animals but can be unicellular or multicellular.
- Yeast is a unicellular fungus used in bread making; mushrooms are multicellular fungi.
- Multicellular fungi have thread-like structures called hyphae that spread through soil, plants, or human skin.
- Hyphae produce spores, which spread easily and grow into new fungi.
Fungal Diseases
- Rose black spot is a fungal disease causing purple or black leaf spots, especially in roses.
- Infection causes leaves to yellow, drop off, and reduces the plant’s ability to photosynthesize.
- The disease spreads via water or wind.
- Treatment includes removing and destroying infected leaves or applying fungicides.
Characteristics of Protists
- Protists are eukaryotic organisms that can be single-celled or multicellular, mostly unicellular.
- Some protists are parasites, living on or in other organisms and harming them.
- Protists are often transmitted by vectors—organisms like insects that carry them between hosts without getting sick.
Protist Diseases: Malaria Example
- Malaria is caused by a parasitic protist, requiring a host to survive.
- Mosquitoes act as vectors, transferring malaria between humans or animals by feeding.
- Malaria symptoms include recurrent high fevers, headaches, and can be fatal.
- Prevention includes reducing mosquito populations, using insecticides, and mosquito nets or repellents.
Key Terms & Definitions
- Eukaryotic — organisms with cells containing a nucleus and organelles.
- Unicellular — made of a single cell.
- Multicellular — made of more than one cell.
- Hyphae — thread-like structures in fungi for growth and spreading.
- Spores — fungal reproductive cells that spread and grow into new fungi.
- Parasite — an organism that lives on or in a host, harming it.
- Vector — an organism that transmits pathogens but does not get sick itself.
Action Items / Next Steps
- Review examples of fungal and protist diseases.
- Practice identifying methods to prevent the spread of these diseases.
- Study definitions of key terms for exams.