Fish anatomy consists of several key parts that help them survive in aquatic environments. The body is streamlined for efficient swimming, with fins that aid in movement. The gills allow fish to extract oxygen from water, while the scales provide protection and reduce water resistance. Internally, fish have a swim bladder that helps them maintain buoyancy. Their heart pumps blood through a single circulatory system, and the digestive system processes food, starting from the mouth and ending at the anus. Overall, these anatomical features are essential for a fish's survival and adaptation to their habitat.