Chemical senses and Multisensory Integration Flashcards
What are the 2 main chemosenses in humans?
Taste and Smell
Gustation is a scientific word for…?
Taste
Olfaction is a scientific word for…?
Smell
What is a more scientific word for smell?
Olfaction
What is a more scientific word for taste?
Gustation
What do chemosenses do?
Detect chemicals
How can taste and smell have a survival value?
They prevent ingestion of toxins and avoid danger
What are the social effects of smell?
Pheromones
(Pheromones are substances which are secreted to the outside by an individual and received by a second individual of the same species; they induce activity in other individuals)
What are the 5 core tastes?
1) Sweet
2) Sour
3) Salty
4) Bitter
5) Umami
What is umami taste?
Savoury
Each taste bud cell contains…….. that respond to each of the 4 tastes
Taste receptors
How many taste buds do humans have?
9000-10000
Different areas of the tongue more responsive to the core tastes
True or False?
False. This is an old view.
What causes sweet tastes? List 2 things
1) Sugars (fructose, glucose, saccharose…)
2) Artificial sweeteners (aspartame, saccharin…)
What causes sour tastes? List 1 thing
All acids (acetic acid, citric acid, ascorbic acid, phosphoric acid, lactic acid…)
What causes bitter tastes? List 4 examples
No unique chemical class:
1) Quinine
2) Caffeine
3) Peptide
4) Phenols
What causes salty tastes? List 1 thing
Salts like table salt (NaCl) or NH4Cl, KCl
What causes umami tastes? List 3 examples
1) Mono sodium glutamate
2) Inosine 5’- monophosphate
3) Guanosine 5’-monophosphate
Saccharin causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
c. Sweet
Quinine causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
b. Bitter
Guanosine 5’-monophosphate causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
d. Umami
Aspartame causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
c. Sweet
Peptide causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
b. Bitter
Ascorbic acid causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
e. Sour
Phenols causes what taste?
a. Salty
b. Bitter
c. Sweet
d. Umami
e. Sour
b. Bitter
What is the difference in tongue between super tasters and normal tasters? List 3 points
- Supertasters have more papillae on their tongues
- Meaning they have a more sensitive tongue
- They also have more taste buds
What % population qualifies as supertasters?
25%
What do large amounts of papillae on the tongue help supertasters do?
Detect ‘tasteless’ substance PROP (6-n- propylthiouracil)
Some researchers suggest the existence of a sixth taste. What taste is it?
Starch taste
Why is detecting starch tastes important?
It may be important for detection as a slow-release form of energy
Olfaction (smell) can discriminate up to ………. types of molecules?
10,000
What is smell limited by?
Limited by our memory for what they indicate
Is there a satisfactory classification of odours?
No
What are the 2 routes of smell?
1) Orthonasal
2) Retronasal
What is the orthonasal route of smelling?
We smell chemicals by inhaling/breathing in through our nose and into the olfactory membrane
What is the retronasal route of smelling?
We smell chemicals during chewing and swallowing. The smell comes from the back of our mouth and into the olfactory membrane
Which route of smell is this?
We smell chemicals by inhaling/breathing in through our nose and into the olfactory membrane
Orthonasal (via inhalation)
Which route of smell is this?
We smell chemicals during chewing and swallowing. The smell comes from the back of our mouth and into the olfactory membrane
Retronasal (during chewing and swallowing)
How many different types of olfactory receptors do humans have?
350
What can olfactory receptors do?
They are able to discriminate large number of different smells
They are able to discriminate a large number of different smells
These are known as…?
Olfactory receptors
How do olfactory receptors work?
1) Odorants bind to the olfactory receptors
2) Olfactory receptor cells are activated and send electrical signals
3) The signals are relayed in glomeruli
4) The signals are transmitted to higher regions of the brain
True or False?
Olfactory receptors of different types project electrical signals to the same glomerulus
False
Olfactory receptors of similar types project electrical signals to the same glomerulus
How many olfactory stimuli/molecules can humans discriminate?
1 trillion
What are the 3 types of top-down effects on smell?
1) Attention
2) Effect of labelling
3) Effect of learning
How can attention affect smell?
Sniffing something pleasant can catch your automatic attention and make you more likely to do something
e.g. When you want to sell a house, you can bake bread to induce a “bakery” and “homely” smell to attract potential buyers
People would be more likely to buy because of the smell (it smells like home, cosy, comforting)
How can the effect of labelling affect smell?
An odour can smell bad if it is labelled as something bad rather than something not as bad
e.g. The same odour smells worse when labelled as body odour rather than cheese
How can the effect of learning affect smell?
When you have smelt something multiple times, you are able to recognise if it is good or bad
e.g. Expert wine tasters identifying wine odours
When you have smelt something multiple times, you are able to recognise if it is good or bad
e.g. Expert wine tasters identifying wine odours
This is known as…?
Effect of learning on smell
An odour can smell bad if it is labelled as something bad rather than something not as bad
e.g. The same odour smells worse when labelled as body odour rather than cheese
This is known as…?
Effect of labelling on smell