Our body is made up of billions of individual cells, which carry out numerous activities within themselves and interact with one another is a systematic way to produce a harmonious whole body of ourselves.
Considering the complexity of activities and their interactions, it is miracleous that such activities can occur in a small and compact cell.
Look at the videos below to appreciate the complexities and exactness of the various activities occurring within the cells.
A: The wonders of a tiny cell by olemann77
B: The Inner Life of Cell by Abbas92Alamdar
In the Quran, Allah ask us to look at the wonders of His creations on the earth, within ourselves and beyond (outerspace and heavens)
Surat Adh-Dhariyat (51)
verse 21 : And on the earth are signs for the certain [in faith]
verse 22 : And in yourselves. Then will you not see?
verse 23 : And in the heaven is your provision and whatever you are promised.
For full translations of Surat Adh-Dhariyat (The Winnowing Winds) please visit the site (Sahih International) at http://quran.com/51