Answer to Question #216203 in Zoology for KESAVAN L

Question

How does the tissue level of organisation is advanced over the cellular level of organisation

Answer 1

A tissue is a group of similar cells, along with any intercellular substance, which performs a particular function. Some cells, e.g. unicellular protozoans and algae, perform all functions which are essential to life. It is impossible for such cells to be efficient at all functions, because each function requires a different type of cellular organization. Whereas one function might require the cell to be long and thin, another might require it yo be spherical. One function might require many mitochondria, another, very few. Acid conditions might suit one activity but not another. No one cell can possibly provide the optimum conditions for all activities. For this reason, cells are specialized to perform one, or at most a few, functions. To increase efficiency, cells performing the same functions are grouped together into a tissue.