Lets see some of the similarities between unicellular and multicellular organisms here on this page:
Similarities between Unicellular and Multicellular Organisms
1. The main similarities between Unicellular and Multicellular Organisms is that both contain DNA and ribosomes.
2. Both Unicellular and Multi cellular Organisms exhibit similarity in the functions of metabolism and reproduction.
3. Both are essential to almost every ecosystem that we currently know or live in.
4. Both need a control center to guide them. So they have a nucleus.
5. Both have cytoplasm and cell membrane.