Question

airborne chemical substances travel up the nose to the olfactory ________, which is the receptor for smell.
a. cilia
b. cortex
c. bulb
d. base

please select the best answer from the choices provided

a
b
c
d

Explanation:

Identify the anatomical structure acting as the receptor for smell

Airborne chemical molecules (odorants) enter the nasal cavity and bind to receptor proteins on the hair-like projections of olfactory receptor neurons. These microscopic, hair-like structures are called olfactory cilia.

Evaluate the given options

• A. cilia: Olfactory cilia contain the actual receptor proteins that detect airborne chemical substances.
• B. cortex: The olfactory cortex is a brain region that processes olfactory information, not the receptor itself.
• C. bulb: The olfactory bulb receives neural signals from the olfactory receptor cells and sends them to the brain; it is not the initial receptor.
• D. base: This is not a standard anatomical term for the primary olfactory receptors.

Answer:

• A. cilia (Correct answer)
• B. cortex
• C. bulb
• D. base