Cell Basic unit of life|Unicellular and multicellular organism#!#Discovery of cell

Give one example each of unicellular and multicellular organism.

Compare unicellular and multicellular organisms, with one example.

Is sieve tubes unicellular or multicellular ?

Introduction || Branches OF cell biology || Unicellular& Multicellular organisms || History OF cytology || Cell theory

Introduction ,branches OF cell biology;unicellular& multicellular organisms;history OF cytology;cell theory