The stem cells that are initially formed in the body undergo differentiation through various chemical signals that drive them to differentiate into appropriate cell types.
Step-by-step explanation:
The two haploid gelametic cells fuse to form a diploid cell which is got as a zygote. This zygote is a simple cell that undergoes repeated mitotic divisions to form different cellular organelles.
The cells that are differentiated into a particular type thereby they are differentiate into different organ systems according to the chemical signals that are received by the receptors of the cell.