special senses- the chemical senses pt 1

what are the 5 special senses?

1. Taste-gustation

2. smell—olfaction

3. hearing

4. equilibrium

5. vision

which two special senses are considered chemical senses?

Gustation and olfaction

what kind of environmental stimulus activates the chemical senses?

chemical molecules from food (taste) or air (smell)

what bodily systems do the chemical senses affect besides sensory perception?

Gastric secretion, blood flow for digestion, insulin secretion, and metabolism

True or false: taste and smell only influence flavor and food preference

False—they also affect digestion, blood flow, insulin, and metabolism

what is gustation?

the sense of taste; detection of molecules dissolved in water (saliva)

what are the chemical molecules that trigger taste called?

Tastants

where are taste buds located?

mainly on the tongue, but also on cheeks, soft palate, pharynx, and epiglottis

True or false: when you look at your tongue, you can see your taste buds

False; you are looking at tongue papillae, the taste buds are inside these papillae

what must happen before a molecule can be tested?

It must dissolve in saliva and flood the taste pore

what taste is triggered by metal ions like sodium and potassium?

salty

which primary taste is associated with high-caloric carbohydrates?

sweet

what triggers the umami taste?

amino acids (like those in chicken broth or soy sauce)

what kind of chemicals cause bitter taste?

spoiled foods and alkaloids (nicotine, caffeine)

True or false: water and fats are officially recognized as primary taste sensations.

False

what types of tastes use G-protein-coupled receptors?

Sugars (sweet), alkaloids (bitter), and glutamate (umami)

what types of tastes depolarize cells directly without using second messenger systems?

Sodium (salty) and Acids (sour)

which is faster, G-protein coupling receptors or direct depolarization by entering the cell directly?

Direct depolarization (salty/sour)

what cranial nerves carry taste signals?

Facial (VII), Glossopharyngeal (IX), and Vagus (X)

where do first-order gustatory neurons start and end?

cranial nerves to the medulla oblongata

which brain areas control salivation and gagging?

Hypothalamus and amygdala

where is the conscious perception of taste processed?

Gustatory Cortex

Where is the emotional response to taste processed?

orbitofrontal cortex

taste perception pathway, the medulla oblongata is the?

2nd-order neuron

in taste perception pathway, the thalamus is the?

3rd order neuron

in taste perception, the hypothalamus and amygdala produce?

the physical reaction like salivation or gagging

in taste perception, the gustatory cortex produces?

the perception of taste

in taste perception, the orbitofrontal cortex produces the?

emotional response