There are a few characteristics that are common to all multicellular organisms. 

• By definition, they are made up of more than one cell. 
• Multicellular organisms are complex and possess distinct organs and organ systems, each of which performs a distinct function. 
• They contain membrane-bound structures and are classified as eukaryotes. 
• They are visible to the naked eye and grow in size as the number of cells increases. 
• Their cells exhibit division of labor.