How is the division of labour at various levels of organisation in multicellular organisms correlated with their structure and function? [Pg. No. 28]

In multicellular organisms, different cells are specialised to perform specific functions. Similar or dissimilar cells form tissues, different tissues combine to form organs, and organs work together in organ systems. This organisation creates a division of labour in which each level performs a particular function efficiently. For example, muscle cells are specialised for movement, muscle tissues form muscles, and muscles work with bones to bring about body movement. Thus, the structure of cells, tissues, organs and organ systems is closely related to the functions they perform, ensuring efficient functioning of the organism.