The key difference between capsid and capsomere is that capsid is the protein coat that surrounds and protects the viral genome while capsomere is the structural subunit of a viral capsid and aggregation of several protomers as a unit.
Viruses are intracellular parasites. They all are infectious and cause different types of diseases to plants, animals, protists, bacteria and fungi. There are two main components that make a virus. They are the protein shell and the nucleic acid genome. Protein shell, also known as the capsid, is made up of proteins. The main function of the capsid is to protect the viral genome and aid in the infection process. A capsid consists of capsomeres, which are the structural and morphological subunits of the viral capsid. Capsomeres self assemble nicely and give shape to the viral capsid in each virus particle. Structurally, capsomere is an aggregation of several protomers as a unit.
