Receptors are sensory structures (organs/ tissues/ cells) that detect changes in the environment, which are called stimuli, and turn them into electrical impulses to be transferred to the brain. The tongue has taste buds which can detect chemicals in food and identify taste. Hence, it is considered as receptor. Effector is an organ that responds to stimulus. The tongue is a muscular organ that can respond to a stimulus. Hence, it is also considered as an effector organ.