Question

why in unicellular forms growth and reproduction are synonymous?

Answer 1

Growth is defined as increase in mass and size during the development of an organism over a period of time.
Reproduction is the process of production of progeny possessing features more or less similar to their parents in multicellular organisms.
but when it comes to unicellular organisms like bacteria, unicellular algae or Amoeba
reproduction is synonymous with growth, i.e., increase in number of cells.

Answer 2

In unicellular organisms like yeast or amoeba, increase in cellular size leads to cell division which creates to new offsprings. Hence , in unicellular organisms growth is same as reproduction because increase in mass and size of the body is leading to the generation of two new daughter cells and so on.

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