Some harmful protists include plasmodium, gregarines, haemosporidia and coccidians. Others include babesia, toxoplasma, adeleorina and some forms of amoeba. Some of these protists are parasites on invertebrates such as gastropods while others are parasites on vertebrates such as humans.
Plasmodium is a protist that causes malaria. The organism is passed from one host to another either by a mosquito or, more rarely, through sharing of contaminated needles. This happens because the parasite needs to spend part of its life cycle inside the mosquito and part of its life cycle inside a vertebrate. The sickness is caused because the organism invades the host's red blood cells and deforms them. This is why sickle cell anemia, where the red blood cells are already deformed, offers some protection against malaria.
Coccidians and gregarines live in the guts of their hosts, but coccidians parasitize vertebrates, while gregarines are found in mollusks and types of arthropods. Both of these protists also have complex life cycles that require a host to complete. Coccidians cause diseases such as cryptosporidiosis and cyclosporiasis.
The entamoeba histolytica is responsible for amoebic dysentery. They also live in the gut and destroy the bacteria that live there. This causes symptoms such as constipation that alternates with bloody, watery diarrhea, flatulence and abdominal cramps.Learn More
One way in which protists are considered primitive is that they are mostly unicellular, and the ones that are multicellular do not organize their cells into specialized tissues. However, protists have been evolving just as long as other life on Earth and are not necessarily primitive beings.Full Answer >
The types of protists, which are eukaryotes, that aren't animals, fungi or plants include euglenoza, alevolates, stramenopiles, red algae, slime molds and choanoflagellates. The alevolate group includes ciliates, sporozoans and dinoflagellates. The stramenopile group includes diatoms, golden algae, green algae and water molds.Full Answer >
Various protist species are important to humans because they are the primary producers at the base of the food pyramid, turning the energy from the sun into a form that can be passed from organism to organism up the food pyramid. Protists also stabilize the ion levels of water, which allows seaweed and fish, both of which are important food sources for humans, to thrive.Full Answer >
Protists are a diverse group of organisms, and they reproduce in a number of different ways, including asexual binary fission, multiple fission, fragmentation and several forms of sexual reproduction. Many protists can reproduce either sexually or asexually depending on environmental conditions.Full Answer >