Taste Buds Flashcards

Explore taste bud anatomy, including their distribution, sensory cell types, taste pores, receptor mechanisms, innervation, and regeneration.

Card 1 of 30Question

What are taste buds?

Specialized sensory structures within the oral and pharyngeal epithelium that detect dissolved chemical substances.

In This Section

1. What are taste buds?

Specialized sensory structures within the oral and pharyngeal epithelium that detect dissolved chemical substances.

2. What is the primary sensory function of taste buds?

Gustation, the detection of chemical stimuli responsible for taste.

3. Where are taste buds primarily located?

In fungiform, circumvallate, and foliate papillae of the tongue.

4. Which type of lingual papilla normally lacks taste buds?

Filiform papillae.

5. Where are taste buds found outside the tongue?

In parts of the soft palate, oropharynx, and epiglottic region.

6. What is the characteristic histological shape of a taste bud?

An oval or barrel-shaped collection of elongated epithelial sensory and supporting cells.

7. What are the principal cellular populations within a taste bud?

Type I, Type II, Type III, and basal progenitor cells.

8. What is the primary role of Type I taste bud cells?

They provide glial-like support and help regulate the extracellular environment.

9. Which taste bud cells detect sweet, bitter, and umami stimuli?

Type II receptor cells.

10. Which taste bud cells are primarily responsible for detecting sour stimuli?

Type III presynaptic cells.

11. What is the role of basal progenitor cells associated with taste buds?

They generate replacement taste bud cells during normal epithelial renewal.

12. What is the taste pore?

A small opening at the epithelial surface through which taste cell microvilli contact dissolved tastants.

13. What structures project from taste receptor cells into the taste pore?

Apical microvilli.

14. What are the five widely recognized basic taste qualities?

Sweet, sour, salty, bitter, and umami.

15. What type of receptors primarily mediate sweet, bitter, and umami taste?

G protein-coupled receptors.

16. Which ion is the principal chemical stimulus for sour taste?

Hydrogen ions (H+).

17. Which ion is principally associated with salty taste?

Sodium ions (Na+).

18. Which neurotransmitter is released by Type II taste receptor cells?

Adenosine triphosphate (ATP), which activates purinergic receptors on gustatory nerve fibers.

19. Which neurotransmitter is characteristically released by Type III taste cells?

Serotonin.

20. How frequently are taste bud cells generally renewed?

Many are replaced within approximately 10 to 14 days, although turnover varies among cell types.

21. Which nerve carries taste sensation from most of the anterior two-thirds of the tongue?

The chorda tympani branch of the facial nerve (cranial nerve VII).

22. Which nerve carries taste sensation from the posterior third of the tongue?

The glossopharyngeal nerve (cranial nerve IX).

23. Which cranial nerve carries taste sensation from the circumvallate papillae?

The glossopharyngeal nerve (cranial nerve IX), despite their position anterior to the sulcus terminalis.

24. Which nerve carries taste sensation from the epiglottic region?

The internal laryngeal branch of the superior laryngeal nerve, derived from the vagus nerve (cranial nerve X).

25. Where are the cell bodies of taste fibers traveling in the facial nerve located?

The geniculate ganglion.

26. Where are the cell bodies of glossopharyngeal gustatory sensory neurons located?

The inferior glossopharyngeal (petrosal) ganglion.

27. Where do primary gustatory afferent fibers terminate in the brainstem?

The rostral gustatory portion of the nucleus of the solitary tract in the medulla.

28. Which thalamic nucleus relays gustatory information toward the cerebral cortex?

The parvicellular portion of the ventral posteromedial nucleus.

29. Where is the primary gustatory cortex located?

Primarily in the anterior insula and adjacent frontal operculum.

30. Why can injury to the chorda tympani cause altered taste sensation?

It interrupts gustatory afferent fibers from taste buds in the anterior tongue.