[Campbell Biology P.1173] Which of the following statements accurately differentiates human g... | Practice Question

Which of the following statements accurately differentiates human gustation taste from olfaction smell according to the text?

  • A: Both taste and smell sensory cells are classified as neurons.
  • B: Olfactory receptor cells transmit impulses directly along their axons to the olfactory bulb, unlike taste receptor cells.
  • C: Humans possess significantly more distinct receptor genes for taste than for smell.
  • D: Olfaction primarily involves ion channels for signal transduction, while taste exclusively uses GPCRs.

Explanation

The text states: 'In olfaction, unlike gustation, the sensory cells are neurons. Olfactory receptor cells line the upper portion of the nasal cavity and send impulses along their axons to the olfactory bulb of the brain'. This directly supports statement B. The other options contain inaccuracies as per the text e.g., taste cells are modified epithelial cells, not all tastes use GPCRs, and humans have far more OR genes than taste receptors .