One very diverse group of eukaryotic microbes are protozoa. All protozoa are eukaryotic, unicellular and lack cell walls. Many protozoan are chemoheterotrophs, getting energy and carbon from other organsims. Two groups of protozoans that are photosynthetic are dinoflagellates and euglenoids. Protozoans are divided into six groups: Parabasalids have a Golgi like organelles, a parabasl body, and lack mitochondria. Examples: are 1. Trichonympha which live in the guts of termites and digest cellulose into glucose. 2. Trichomonas which lives in the acidic environment of the human vagina, if the pH is increased, it can proliferate and cause inflammation which might lead to sterility. Diplomonadida lack mitochondria and have two rudimentary mitochondria called mitosomes, two equal size nuclei and multiple flagella. An example of this type of protozoan found in well water or lake water if Giardia, the ingestion of cysts leads to a GI infection characterized by flatulence and diarrhea. This protozon looks owl like in a light microscope because of the two nuclei. Euglenoza Euglenids:lack cell walls, have flagella, are chemoheterotrophic phagocytes in the dark, and have several features unique to euglenids. For one they store energy in a polysaccharide paramylon. They may move by a squirming motion called euglenoid movement. They have a protein pellicle under thier plasma membrane to give the cell shape. Most have a "red eyespot" that helps with phototaxis. Kinetoplastids have a single large mitochondria that contain a kinetoplast Two notable pathogens in this group are Trypanosoma and Leishmania. Alveolates have small membrane bound cavities beneath the plasma membrane called alveoli. In addition, alveolates have tubular mitochondria cristae. There are three subgroups. Ciliates have cilia for motility or to move water past the cell surface. Ciliates are chemoheterotrophic and have two nuclei. The only pathogenic ciliate is Balantidium. Paramecium is a well known pond dweller used to study regeneration. Apicomplexans are chemoheterotrophic animal pathogens. They contain apices which are organelles that contain enzymes that allow the protozoan to penetrate host cells. Three examples of apicomplexans are Plasmodium, cryptosporidium and Toxoplasma.
12. According to CDC toxoplasmosis is a neglected parasitic disease. Cats play an significant role in transmitting the protozoan because cats become infected by eating infected rodents or birds. An infected kitten may shed as many as a million cysts in thier feces for up to 3 weeks after infection. Humans may become infected by changing cat litter boxes or gardening without gloves. Suggest at least two ways a person may prevent infection based on this information. You may also visit the CDC websitehttps://www.cdc.gov/parasites/toxoplasmosis/gen_info/pregnant.html (Links to an external site.)Links to an external site..
