What is the significance of sharks and rays in nature and human life?

Sharks and rays are cartilaginous fish and have a certain value in nature and human life. They are an integral part of the marine ecosystem and occupy different places in the food chain. Sharks regulate the number of marine life and, together with stingrays, are a valuable product of the fishery. They have everything valuable: meat and fins (for food), skin (in the leather industry), fat, liver (in medicine), even the skeleton is used for the production of fertilizers and glue.

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