According to biologist Robert Sapolsky, what makes you you--that is, your DNA--isn't a 50/50 split between your mother and father. He says that, "you get a disproportionate share of your DNA coming from your mom."
Biologist and YouTube member cadamole explains how in this touching homage to his mother:
I got so much more from you mom
Than just half a set of genes
I got nutrients and transcription factors
and nearly everything that matters
plus my prenatal environment (transplacental inheritance)
That back in the day once belonged to ya (theyre cytoplasmic)
and I just want to thank for supplying them
Just like two strands of DNA are spirally entwined
Your nature and your nurture are inspiringly combined
Scientists remind me and I find that it is true
Slightly more than half of everything I am is thanks to you
You can read the complete lyrics here.
-via VA Viper