human
Can you tell me the difference between a bacterium, a virus, a fungus and a parasite?
assistant
A bacterium is a single-celled microorganism that can be found in almost every environment. Bacteria are often referred to as “prokaryotes” because they do not have a cell nucleus and therefore lack the ability to reproduce sexually. Viruses are much smaller than bacteria and consist of only one type of genetic material (DNA or RNA). They replicate themselves by inserting their genetic material into host cells. Fungi are also single-celled microorganisms but they differ from bacteria in that they produce spores which allow them to survive harsh conditions. Parasites are organisms that live off other living things, usually animals. They may be either microscopic or macroscopic.