Classification of viruses

Classification of viruses Student name Course Institution Instructor Date due The five kingdoms of life are identified as: plant, fungi, animal, moneran and fungus. Plants are many celled organisms and there are about a quarter million plant species. The animal kingdom has a variety of known animal species, about one million (Campbell, 2003). They are complex organisms with many cells and are divided into vertebrates and invertebrates. Monerans are one-celled organisms and do not have a nucleus. This kingdom is mostly composed of bacteria that are further grouped into bacteria and cyanobacteria. In addition, bacteria are the most common organisms on earth. Protists include various groups. Most are one-celled while few others are many celled. There are about 38,000 known protist species. They live in water and some move around while others stay in one place. They include algae, paramecium and amoeba. Fungi may also be one-celled or many celled organisms. They include yeast and mould and are known as decomposers (Edwards, 1990). Viruses are defined as submicroscopic particles that can infect other organisms and are composed of a protein coat and a nucleic acid (Edwards, 1990). This structure is suited to the virus function which is to enter a host cell and reproduce. Some viruses have outer membranes that enable the virus to infect the cell easily. Like cells, viruses carry genetic information that is encoded in their nucleic acid and mutate and reproduce but they do not carry out metabolism and thus are not alive. They cannot survive outside a host cell and this is where they have to reproduce. They infect all types of cells such as plants, animals but they usually ...