Establish similarities and differences in the structure of unicellular and multicellular organisms?

Many species on Earth are unicellular, meaning they only have one cell. All animal and plant species, however, are multicellular, which means they have multiple cells. Both unicellular and multicellular organisms share some important similarities, such as their genetic code. The cells in a multicellular organism must work together to a greater extent than single-celled organisms, so there are some important differences.

With a few rare exceptions, almost all types of multicellular organisms are eukaryotes, and their DNA is contained in a special structure called the nucleus. Eukaryotes usually also possess membrane structures called organelles, which perform functions critical to cell survival and growth. Some unicellular organisms, such as amoeba, are also eukaryotes, but many others are prokaryotes (such as bacteria).