Arrange the following physiological events involved in the perception of smell (olfaction) in a mammal in the correct sequential order from initial stimulus entry to brain perception.
- 1Odorant molecules dissolve in the layer of mucus covering the olfactory epithelium.
- 2Odorant molecules bind to specialized receptor proteins on the cilia of olfactory sensory neurons.
- 3Nerve impulses travel along sensory nerve fibers through the cribriform plate to the olfactory bulb.
- 4Nerve impulses travel along the olfactory tract to the olfactory cortex of the brain for interpretation.
Answer
The correct sequential order is: (1) Odorant molecules dissolve in the layer of mucus covering the olfactory epithelium, (2) Odorant molecules bind to specialized receptor proteins on the cilia of olfactory sensory neurons, (3) Nerve impulses travel along sensory nerve fibers through the cribriform plate to the olfactory bulb, and (4) Nerve impulses travel along the olfactory tract to the olfactory cortex of the brain for interpretation.
Olfaction begins when airborne odorants dissolve in nasal mucus. The dissolved chemicals bind to membrane receptors on olfactory cilia, generating nerve impulses. These impulses pass via sensory axons into the olfactory bulb and subsequently along the olfactory tract to the brain's olfactory cortex for processing.
Step-by-Step Solution
Key Concept
Olfactory transduction and neural pathway of smell perception.