Except for identical twins, all the other human beings are genetically distinct from each other. why is this true?

It's because of sexual reproduction,
this causes everyone to get unique DNA patterns, (except for twins, which from by one fertilised egg splitting into 2). 50% from mum 50% from dad

When ever the sex cells go through reproduction,  our 46 cells come together to make about .01% of us, in that is everything about us, eye color, skin color, hair color, emotions. So really we all are barely different.

Need a picture to do this

The arrangements of lipids in the membrane makes the cell semi permeable .