Question

The Zygote is single celled and a human adult has about hundred trillions approximately how many divisions today's I got under go to form the adult considering the fact that one cell division led to the formation of two cells

Answer 1

The zygote undergoes cell division, or mitosis, in order to develop into an organism of trillions of cells. It also undergoes speciation early on in the development of the organism. In order to create an organism with 100 trillion cells, 50 trillion cells need to divide (one time of mitosis), and 25 trillion need to divide to make 50 trillion (two times of mitosis), and so on. The cell would have to repeat this process 40 times (one cell going under mitosis 40 times is equivalent to 1 times 2 to the 40th power, which equals 1 trillion)

Answer 2

Cell division:

A zygote is a product of fertilisation between two gametes.

From question,

Division of 1 cells = 2 daughter cells

Number of cells in adult = hundred trillions (approx) $\bold{=1\times10^{14}}$

Number of division the adult has to undergo is:

$\bold{Number \ of \ division =\frac{1\times10^{14}}{2}=5\times10^{13}=50\times10^{12}=50\ billion}$

A zygote has to under 50 billions division to form a human adult only if one cell is divided into two cells.