Cyanobacteria don't need oxygen to survive they produce oxygen. They where the first ever known organisms on the planet and they produced oxygen in the oceans which was absorbed by iron deposits and then once the iron had oxygen the ocean got the oxygen until it got into the atmosphere and Eukaryota bacteria evolved. So the answer would be: <span>They convert nitrates from the water into nitrogen gas (N2) that is released into the atmosphere.</span>
The term organic, as related to compounds, would be best defined as a compound that contains chain of carbon and hydrogen atoms which are bonded covalently. Common other atoms that could be included are hydrogen, nitrogen and oxygen.
Single celled organisms such as amoebas, especially those that live in fresh water, continually gain water from their surrounding environment by osmosis. This water is pumped into a contractile vacuole which fills with fluid and periodically fuses with the cell membrane, releasing its contents to the exterior. Thus the amount of water actively transported out of the cell is equal to the amount of water entering the cell due to osmosis and there are no variations in the tonicity of the cell. This is homeostasis at a simple level. Without the contractile vacuole, the amoeba would continue to absorb water until its cytoplasmic contents were diluted to such an extent that metabolism no longer occurred and it would die.
Enfermedad que se puede transmitir muy rápidamente de una persona a otra por medio de contacto directo (al tocar a una persona que tiene la infección), contacto indirecto (al tocar un objeto contaminado) o por contacto con gotitas (inhaladas cuando una persona que tiene la infección tose, estornuda o habla).
Un ejemplo de una enfermedad sería el sida es transmitido por actividad sexual desprotegida o por contacto de la sangre o de la saliva de la persona con sida hacia alguien con una herida
Espero ayude :)
