Asked by: Adam Stephens, Salisbury
A big challenge facing squid in the deep sea is keeping their cells working. Under high pressure, important molecules like proteins in cell membranes and enzymes become squashed and bent out of shape and either work more slowly or not at all. One way squid counteract this is by loading their bodies with trimethylamine oxide or TMAO, which helps large molecules keep their shape. For many deep sea animals, the deeper they live the more TMAO they have in their bodies. TMAO also gives rise to the distinctive fishy smell of many sea creatures – the deeper the species lives, the more it smells.
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