Viruses cannot carry out any function without a host cell. They consist of a protein coat around nucleic material.
Bacteria have a cell wall, no nucleus and are often uni-cellular. They reproduce by binary fission. Before they divide, an exact copy of the DNA is made. The cell then divides in two so that each half has one complete set of DNA.
Fungi are saprophytic, mostly multi-cellular, and have cell walls and nuclei. They reproduce using spores. Cells inside a sporangium divide asexually to produce spores. These get released from the sporangium and are carried through the air to land at a new location. Here they will germinate and develop into mycelium.
Nutrition is the taking in of substances which are organic and contain mineral ions, providing energy for growth and repair, which are absorbed and assmiliated.
Proteins are made of Nitrogen, Oxygen and Carbon. They consist of many monomer units called amino acids. …