The term for bacteria that can survive without oxygen is anaerobic bacteria. These organisms thrive in environments lacking oxygen and can obtain energy through processes such as fermentation or anaerobic respiration. Anaerobic bacteria are significant in various ecological roles, including helping decompose organic matter in oxygen-poor environments, such as deep soil or underwater sediments. Some anaerobic bacteria are also utilized in biotechnology and industry, such as in the production of biofuels and in wastewater treatment, highlighting their importance in both natural and human-managed ecosystems.