Comment by pfdietz

The chirality of biomolecules is also the source of the differentiation of left and right in a developing embryo.

Cilia form that are tilted toward the tail of the embryo. The chirality of the protein motors driving them causes them to turn clockwise, which creates a leftward flow of water.

https://pmc.ncbi.nlm.nih.gov/articles/PMC1180515/

https://hms.harvard.edu/news/telling-left-right-organ-develo...