What biological process causes methylmercury to build up in fish tissues over their lifespan?

Answer

Bioaccumulation

Bioaccumulation is the specific process by which methylmercury builds up in the tissues of a fish over the course of its life. Fish absorb this mercury compound from the water they inhabit and from the food they consume. Because larger, longer-lived predatory fish, such as King Mackerel, have extended lifespans, they provide more time for this compound to concentrate in their tissues, resulting in higher overall concentrations compared to smaller or shorter-lived species.

What biological process causes methylmercury to build up in fish tissues over their lifespan?
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