CBSE Class 8 Answered

Cells are of different shape, size and structure according to the function they need to perform. Specialised groups of differentiated cells form tissues. Tissues are made up of similar cells that carry out a common function. For example, muscle tissue is made up of many muscle cells grouped. There is a change in the morphology of the cells when they differentiate to form a particular tissue. As a result, the shape and size of organisms differ. If all the cells were of same shape and size, it will be very difficult for multicellular organisms including humans to adapt better to the environment and survive.