Unicellular organisms have just one cell which performs all the functions such as nutrition , respiration , excretion etc.they are amoeba ,bacteria etc. Multicellular organisms have specialised cell for each purpose as they have millions of cell. They are humans .
Unicellular::these organisms have only one cell(uni) which is responsible for all the activities..these can't be much larger/complex bcoz these have only one kind of cell...if this cell is injured it can cause death of that span will be short due to the heavy work................ Multicellular::: these organisms have many numerous cells.different cells perform different span is long.these can be larger and complex bcoz these have many cells performing many functions...these cells have double roles one for the cells one for the organism....... Hope this helps pls mrk as brainliest...
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