Olfactory Nerve Flashcards

Study the olfactory nerve's sensory receptors, nasal pathways, olfactory bulb connections, and anatomical basis of smell.

Card 1 of 25Question

What is the numerical designation of the olfactory nerve?

Cranial nerve I (CN I).

In This Section

1. What is the numerical designation of the olfactory nerve?

Cranial nerve I (CN I).

2. What is the primary function of the olfactory nerve?

Transmission of special sensory information responsible for the sense of smell.

3. What is the functional classification of the olfactory nerve?

Special visceral afferent (SVA).

4. Where are the olfactory receptor neurons located?

In the olfactory epithelium of the superior nasal cavity.

5. Which regions of the nasal cavity contain olfactory epithelium?

The roof of the nasal cavity, superior nasal concha, and adjacent upper nasal septum.

6. What type of neurons serve as olfactory receptor cells?

Bipolar sensory neurons.

7. Which structures on olfactory receptor neurons detect odorant molecules?

Nonmotile olfactory cilia extending into the mucus layer.

8. What are the small bundles of olfactory receptor axons called?

Olfactory fila, collectively forming the olfactory nerve.

9. Through which part of the skull do olfactory nerve fibers pass?

The foramina of the cribriform plate of the ethmoid bone.

10. Where do olfactory nerve fibers terminate after entering the cranial cavity?

In the olfactory bulb on the inferior surface of the frontal lobe.

11. What are olfactory glomeruli?

Spherical synaptic structures in the olfactory bulb where receptor axons contact second-order neurons.

12. Which neurons provide the principal output from the olfactory bulb?

Mitral cells and tufted cells.

13. What structure carries axons from the olfactory bulb toward the cerebral olfactory regions?

The olfactory tract.

14. Into which two major striae does the olfactory tract divide?

The medial and lateral olfactory striae.

15. Which olfactory stria carries the principal projection to the primary olfactory cortex?

The lateral olfactory stria.

16. Which cortical region is a major component of the primary olfactory cortex?

The piriform cortex.

17. What distinguishes the olfactory pathway from most other sensory pathways?

Olfactory information reaches primary cortex without an obligatory initial thalamic relay.

18. Which supporting cells maintain the environment of olfactory receptor neurons?

Sustentacular cells of the olfactory epithelium.

19. Which cells regenerate olfactory receptor neurons throughout life?

Basal stem cells of the olfactory epithelium.

20. What is the function of Bowman's glands in the olfactory mucosa?

They secrete fluid that helps dissolve and clear odorant molecules.

21. Which type of glial cell ensheathes olfactory receptor axons?

Olfactory ensheathing cells.

22. What is anosmia?

Complete loss of the sense of smell.

23. How can an anterior cranial base fracture damage the olfactory nerve?

By shearing olfactory fila as they traverse the cribriform plate.

24. What complication can occur when trauma fractures the cribriform plate and tears the meninges?

Cerebrospinal fluid rhinorrhea caused by leakage into the nasal cavity.

25. How is the olfactory nerve commonly assessed during a neurological examination?

By asking the patient to identify a familiar, nonirritating odor using each nostril separately.