(a) Endothermic animals are those animals that maintain constant body temperature e.g., mammals and birds like the parrot.
(b) Ectothermic animals are those animals in which the regulations of the body temperature depends on the external environment e.g., reptiles like snake and amphibians like the frog.
(c) Benthic zone is the deepest zone of the ocean e.g., sea anemone.