In the captivating episode "Journey to the Microcosmos: The Beautiful, Brutal Tentacles of Hydra" from the "Journey to the Microcosmos" series, viewers explore the intriguing world of hydras through the lens of advanced microscopy. The video delves into the anatomy and regenerative capabilities of hydras, particularly highlighting their tough yet elegant tentacles equipped with nematocytes. These tentacles, armed with nematocysts, showcase hydra's predatory prowess and their ability to protect themselves from threats. The episode examines historical scientific insights from Abraham Trembley, who famously classified hydras as animals and their contribution to the field of experimental zoology. Key educational terms include regenerative biology, predation, and experimental zoology, which provide enriching content for understanding biological organisms and history of science.