Sensory reception occurs in advanced animals through a procedure identified as transduction, in which stimuli are transformed into nerve impulses and relayed to the brain. The four generally known extraordinary senses (sight, hearing, smell, and flavor) are concerned with the external world, and external stimuli are received and conducted by sensory receptors concentrated in the eye, ear, olfactory organ, and the taste buds. The so-called somatic senses respond to both external and internal stimuli. Even though most of the somatic receptors are located in the skin (assigning the external sensations of touch, heat, cold, pressure, and pain), others are located in internal organs (e.g., the heart and the stomach). Somatic sensations such as starvation, dehydration, and weariness are thought to start off in definite areas of the nervous system. The sense of balance, or equilibrium, is related to the flow of endolymph, a fluid found in the inner ear. (Bahadori, 1993)
Animals react to the messages they obtain from the world aound them. Their reactions to the external world depend on how the data collected from their surroundings are appropriately coded into signals that can be received and processed by neurons in the brain. The sensory organs present the only means of communication from the environment to the nervous system. Sensations occur when signals are detected by sensory receptor cells are transmitted through the nervous system to the designated part of the brain. Various organs and cells are chosen to receive specific stimuli. The main categories of sensory reception addressed here are chemoreception, mechanoreception, and photoreception.
Animals need a regular recognition of information from their surroundings. Such information is the animal’s linkage to the outside world. Sensory effort is primarily detected by sensory receptors. A number of receptors are very intricate, with several individual receptors along with other structures being organized into sensory organs such as the vertebrate eye......
