Biology and Physical Factors #4: Self-Assembly

Self-assembly. It is the “ability” of molecules to assemble themselves into certain shapes. Imagine an ice cream cone shaped molecule with two opposing halves – the ice-cream part is attracted to water (hydrophilic); the cone part avoids water (hydrophobic). Put enough of them in water, and they will automatically arrange themselves to “shield the hydrophobic cones”, writes Raghuveer Parthasarathy in So Simple a Beginning.


 

The base principle here is:

“Molecular shape is a key determinant of self-assembly.”

This is just a physical property. The organism doesn’t need DNA instructions for certain molecules to arrange themselves a certain way!

“The cell does need genes to encode the proteins that synthesize (certain) molecules; once made, the lipids can organize themselves.”

To put it differently:

“Physical simplicity may underlie biological complexity.”


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