FIGURE 3.10 Taste Buds (a) Embedded in the surface of the tongue are thousands of taste buds, the sensory receptor organs for taste. Taste buds are located in the grooves of the bumps on the surface of the tongue. Each taste bud contains an average of 50 taste receptor cells. When activated, the taste receptor cells send messages to adjoining sensory neurons, which relay the information to the brain. Taste buds, like the olfactory neurons, are constantly being replaced. The life expectancy of a particular taste bud is only about 10 days. (b) The photograph shows the surface of the tongue magnified hundreds of times.
Whitemann/Zefa/Corbis