Question

explain '' A cell is a basic unit of an organism"

Answer 1

Structural Unit-Single-celled organisms fulfil all the functions of the organ systems found in a multicellular organisms. Their is no differentiation of organ system in the single-celled oeganisms e.g., Amoeba, although their assigned functions are performed similar to the the functions of an organied multicellular organisms.Fuctional Unit-All the functions such reproduction, respiration etc., are performed in single-celled organisms like a multicellular organisms.So, we can conclude that cells are the structural and functional unit the organisms. 

Answer 2

A cell is a basic unit of an organism because our life starts from a single cell which divide and re divide to give a particular shape to the body. A cell is also called the structural and functional unit of an organism.
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