Three critical aspects of a description of bacterial growth are colony size, color, and shape. At least three other important factors-not physical descriptions-typically are included when describing bacterial growth. What do you suppose they are and why are they so important?
Temperature,time and medium are other three factors which affect the growth of bacteria. The rate at which bacteria grow and divide depends on the nature of the microbe., the ingredients of the medium in which it is grown, and the environmental conditions. For example, E.coli, when grown in a rich medium, with plenty of aeration at 37 degree Centigrade is capable of dividing every 20 min. In contrast, Mycobacterium tuberculosis has a maximum doubling time of about 18 hour and will take much longer than E.coli, for example, to form colonies on an agar plate.