Smell and Taste Flashcards
Describe the structure of a taste bud.
Sensory cells topped with microvilli, support cells are sandwiched either side.
How often are sensory cells replaced in a taste bud?
Every 10 days
What are the four types of papillae?
Fungiform Filliform Vallale Foliate
Of the four papillae which ones contain the most taste buds?
Fungiform Vallale Foliate
What nerve supplies taste for the anterior 2/3rds of the tongue?
Chordi tympani - Branch of the VII facial nerve
What nerve supplies taste for the posterior 1/3 of the tongue?
Glossopharyngeal CN IX
What are the five primary tastes?
Bitter Sour Salty Sweet Umami
What is the umami flavour?
Meaty/savoury
What is Ageusia?
Loss of taste function
List some causes of ageusia?
Never damage
Irradiation
Smoking
What is hypogeusia?
Reduced taste
List some causes of hypogeusia
Platinum based chemotherapy
What is pysgeusia?
Distortion of taste
List some causes of pysgeusia
Glossitis
Tooth decay
Metronidazole
What nerve supplies the olfactory cells within the nose?
Olfactory nerve
What cranial nerve is the olfactory?
CN I
What cells make up the olfactory region of the nose?
Receptor cells
Support cells
Basal cells
What is the function of the basal cells?
Secret mucus
What is special about the olfactory receptor cells?
They have the only renewable afferent neurones, the neurones can grow back once damaged.
Describe a olfactory receptor cell
Extended olfactory rod with cilia on the end.
How does sniffing increase your ability to detect scents?
Draws air and the odorants up to the olfactory cells.
In order to be detected what do odourants need to be?
Volatile and with a high enough concentration to be detected.
