Answer:
Bacteria. These one-cell organisms are responsible for illnesses such as strep throat, urinary tract infections and tuberculosis.
Viruses. Even smaller than bacteria, viruses cause a multitude of diseases ranging from the common cold to AIDS.
Fungi. Many skin diseases, such as ringworm and athlete's foot, are caused by fungi. Other types of fungi can infect your lungs or nervous system.
Parasites. Malaria is caused by a tiny parasite that is transmitted by a mosquito bite. Other parasites may be transmitted to humans from animal feces.
Explanation:
i write it with the explanation on when i answer it
<span>Nitrogen fixation
This process creates organic compounds, including ammonium, that contribute to the growth of a plant in much the way fertilizer does. Many plants have evolved to facilitate nitrogen fixing bacteria in their roots as to promote production of these organic compounds when the soil quality is poor or lacking in these bacteria.</span>
starts with sunlight and photosynthesis if you are talking about plants
