| Unicellular Organisms | Multicellular Organisms |
| Reproductive Cell. The same cell which functions as the body of the organism also gets transformed into reproductive cell. | Specific cells take part in reproduction. |
| Technique. Techniques of reproduction are simple. | Techniques of reproduction are commonly complex |
| Asexual Reproduction. It generally occurs through fission. | It occurs by several methods like. fragmentation, regeneration, budding, spore formation, vegetative reproduction, etc. |
| Sex Organs. No special sex cell or sex organ is present. | They are present. |
| Sexual Reproduction. It occurs through isogamy to heterogamy | It is commonly oogamous. |