Question

unicellular organism also grow by cell division. why not to increase the number of cell in it

Answer 1

Cell division and growth. In unicellular organisms, cell division is the means of reproduction; in multicellularorganisms, it is the means of tissue growth and maintenance. ... Most tissues of the body grow by increasingtheir cell number, but this growth is highly regulated to maintain a balance between different tissues ...

Answer 2

If cells get too large, then metabolic processes like moving things in and out of the cell get much harder. The volume of the cell grows faster than the surface area. To prevent this, cells increase in number to maintain a healthy ratio of volume to SA