Amoebae, slime mold, algae and protactists are some examples of unicellular organisms. Unicellular organisms fall under the main groups of bacteria, archaea, protozoa, single-celled algae and single-celled fungi. The two general categories are prokaryotes, which lack membrane-bound nuclei and membrane-bound organelles, such as mitochondria; and eukaryotes, which are more complex, having membrane-bound organelles and nuclei.Continue Reading
Unicellular organisms are ubiquitous to most environments on Earth. Unicellular organisms have been found in the most extreme environments, such as arid deserts, frozen tundra, highly acidic subterranean environments and hydrothermal vents on the ocean floor; these organisms are called extremophiles. Extremophiles are described by the environments in which they grow optimally, such as acidophilic for acidic environments and thermophilic for environments with high temperatures.
Unicellular organisms can be innocuous to humans, but they are also responsible for diseases. Malaria is caused by a unicellular parasite of genus plasmodium. It is prevalent in tropical and sub-tropical environments. As of 2010, there were an estimated 219 million cases of malaria resulting in 660,000 deaths worldwide. The disease is transmitted from person to person by the bite of the Anopheles mosquito. Prevention includes the use of mosquito nets, pesticides and disruption of mosquito breeding grounds. There are several forms of treatment for malaria as well as ongoing development of a vaccine.Learn more about Biology
Like algae and plants, Euglena cells contain chloroplasts that allow them to create food through photosynthesis, but they can also take in nutrients from other organisms when light is not available. Euglena are a unique group of single-cell organisms that have some of the same functions as both plants and animals.Full Answer >
A coral reef's food chain starts with algae that produce food from water, carbon dioxide and sunlight, which are eaten by microscopic organisms, invertebrates, fish and turtles, which are eaten in turn by predators. All ecosystems, including coral reef ecosystems, have producers, consumers and decomposers.Full Answer >
Examples of monerans include bacteria and blue-green algae. Bacteria are the most populous of all living organisms and critical to life on this planet. As decomposers, they break down organic matter and return the nutrients to the soil for plants to absorb.Full Answer >
Members of the phylum Cyanobacteria, also known as blue-green algae, include oxygenic photosynthetic bacteria, such as Nostoc and Spirulina. Chloroplasts, the organelles responsible for photosynthesis in green plants, are considered to be cyanobacteria that have developed a symbiosis with green plants.Full Answer >