It seems that whenever I am uninspired I turn to science. Science inspires me! So after trying to think esoteric thoughts about layers – layers of the heart, the spirit, personality, onions….I gave up and went with the thought that popped in my head when I first read the daily prompt today.
Lipid bilayer. Yep. That’s today’s topic – the amazing lipid bilayer of the cell membrane. Have you ever wondered how stuff stays inside cells? Each cell is a tiny but highly complex factory with specialized jobs to do and different internal departments assigned to do the tasks. The factory receives its instructions and then sets about in an orderly way completing the order and delivering the products to the appropriate consumers. And the “thing” that keeps the internal cell environment from mixing with the external cell environment is the lipid bilayer.
There are 2 layers of the cell membrane. Lipid molecules have 2 parts – a “hydrophilic” (loves water) head and a “hydrophobic” (hates water) tail. Somehow (I have long-forgotten that biochemistry lecture) 2 rows of lipids align with tails in and heads out forming the barrier between the factory and the outside world.
And stuck in the lipid bilayer wall are all kinds of things you would expect in the “walls” of a factory – doors (proteins, channels, endosomes), antennas, satellite dishes and guidance systems (hormone receptors and sugar/protein side chains), delivery systems (sodium, potassium, calcium channels, pores, carrier proteins), generators (hydrogen channels and ATP synthase molecules), backhaul mechanisms (protein transport channels, synaptic vesicles, carrier proteins) and waste disposal systems (exocytosis, direct diffusion, phagocytosis).
It’s pretty incredible. And that’s just the cell membrane!!! The innerworkings of cells are complicated, ingeniously efficient, highly regulated and coordinated processes that takes PhD-years to learn! And we don’t even know the half of it yet.