Multicellular organisms grow by increasing the number of cells they have. This relies on the processes of cell division and differentiation.Click to see full answer. Keeping this in view, why do larger organisms need to be multicellular?Multicellular organisms can be much larger and more complex. This is because the cells of the organism have specialised into many different types of cells such as nerve cells, blood cells, muscle cells all performing different functions.Subsequently, question is, why don t cells grow larger as organisms grow? Cells are limited in size because the outside (the cell membrane) must transport the food and oxygen to the parts inside. As a cell gets bigger, the outside is unable to keep up with the inside, because the inside grows a faster rate than the outside. Considering this, do organisms grow larger by increasing the size of the cells? Growing is a complex business. Growing is capable to a certain living organism. Growth means getting larger in size, and for multi-cellular organisms this is done by making more cells. Single celled organisms increase their numbers by dividing and making more cells like themselves.Why does the number of cells increase as an organism grows?In cells. The increase in size and changes in shape of a developing organism depend on the increase in the number and size of cells that make up the individual. Increase in cell number occurs by a precise cellular reproductive mechanism called mitosis.
