Spores of fungus, <em>Candida albicans</em> b/w Spores of fungus, <em>Candida albicans</em>

Spores of fungus, Candida albicans

The long strands are the tubular filaments (hyphae) that have developed from the fungal spores. Yeast cells (rounded, yellow) are budding from the ends of the hyphae (red). Candida albicans causes the infection known as candidiasis which affects the moist mucous membranes of the body, such as skin folds, mouth, respiratory tract and vagina. Oral and vaginal conditions are known as thrush.

Protozoa

Protozoa are single celled organisms. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. They live in a wide variety of moist habitats including fresh water, marine environments and the soil.

Some are parasitic, which means they live in other plants and animals including humans, where they cause disease. Plasmodium, for example, causes malaria. They are motile and can move by:

  • Cilia - tiny hair like structures that cover the outside of the microbe. They beat in a regular continuous pattern like flexible oars.
  • Flagella - long thread-like structures that extend from the cell surface. The flagella move in a whip-like motion that produces waves that propel the microbe around.
  • Amoeboid movement - the organism moves by sending out pseudopodia, temporary protrusions that fill with cytoplasm that flows from the body of the cell.