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.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.