JAMB - Biology (2021 - No. 21)
The correct sequence for the perception of smell in mammals is?
chemicals --> olfactory nerve endings --> brain
dissolved chemicals --> nasal sensory cells --> brain
chemicals --> mucus membrane sensory cells --> brain
dissolved chemicals --> sensory cells --> olfactory nerve --> brain
Explication
In mammals(humans), the process of olfaction begins when volatile molecules enter the nasal cavity and activate receptors in the olfactory epithelium (OE). The olfactory receptor (OR) proteins are located in hair-like projections of the olfactory sensory neurons (OSNs).