Final answer:
Taste and smell are the sensory modalities that rely on chemoreceptors to function. They respond to chemical molecules in food and air, respectively, and transmit signals to the brain to be interpreted as flavors or odors.
Step-by-step explanation:
The sensory modalities that depend on the activation of chemoreceptors are taste and smell. These are known as the chemical senses because they have sensory receptors that respond to molecules in food or air.
Taste, also known as gustation, involves chemoreceptors on the tongue that bind with tastants in food. Similarly, smell, or olfaction, employs chemoreceptors in the nose to interact with odor molecules in the air. When these chemoreceptors are activated, they send nerve impulses to the brain, which interprets these signals as specific tastes and smells.
Unlike taste and smell, other senses like hearing, vision, and touch utilize different types of receptors for their function. Hearing and balance are mediated by mechanoreceptors, which respond to mechanical forces, while vision relies on the activation of photoreceptors that respond to light.