These are examples of the single-celled parasites. You can read more about them at examples of protozoa.ĭiseases caused by protozoa include malaria, gingivitis, etc. They are mostly found in fresh water and in slimy moist soil. They can cause diseases in man and other large animals. They have the ability to move and find their food. These are a large class of animals that are visible only under a microscope. Amoeba a protozoa single-celled animal Protozoa But there are few important uses of fungi. But as they grow into a bunch of strands, they can be visible as fluffy material.įungi cause topical infections like ringworm and deranged nails on toes. They can be invisible when present as single strands. They grow on bread and other foodstuffs at home. These are multi-cellular and some of them are microscopic while others are macroscopic. They live in marine and also freshwater environments. They can be seen when they grow in large colonies as patches. These multi-cellular yet microscopic in nature. They differ from bacteria in few biochemical molecules. These are similar to bacteria but live in more harsh conditions and extreme temperatures. They eat up almost anything, due to which the waste gets decayed.īacteria cause many diseases like tuberculosis, leprosy, cholera, etc. They obtain their food by different means like parasitic nature, saprophytic, symbiotic methods, etc. Microscopic view of Listeria monocytogenes. They are called “ prokaryotic cells” due to a lack of a clear-cut nucleus.īacteria are omnipresent, i.e., they can be found on the earth’s surface, underneath, in the air, in the living bodies, etc.