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misogynisticfeminist
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Where do smells come from? How are they formed? Is there any physics behind smells or none at all? can't seem to find any though so far.
Physics of Smells: Where Do They Come From?
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In summary, smells are created when airborne chemicals bind with odor receptors in our nose. This process is mediated by olfactory receptors, which are members of the G-protein-coupled receptor superfamily. The expression of these receptors determines our perception of different smells. Smells can also be context-dependent, meaning our previous experiences and associations can influence how we interpret a particular smell. The amount and sensitivity of these receptors can vary among different species, which may explain why some animals have a better sense of smell than humans. Additionally, chemical properties such as vapor pressure and diffusion play a role in the formation and propagation of smells.
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Integral
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Smells are more physiology and chemistry, so I pop this over to the biology forums. They may have some better answers.
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misogynisticfeminist
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Integral said:
I see...thanks...
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Vance
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Why do you want to know about smells? What are you doing exactly ? I used to ask some questions about smells but I have not got any answers, I would be really angry if someone posts help you outmisogynisticfeminist said:
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Moonbear
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Smells come from the binding of airborne chemicals with odor receptors.
It's kind of late for me here now, so I'm not going to look up any more articles tonight, but I recall from a seminar I attended that odor signals are also context-dependent. In other words, the same odorant chemicals are present in both microwave popcorn and vomit, or possibly it's the same receptors for similar chemicals (I will need to double check the details) , so if you hear the popcorn popping, you smell popcorn, and if you see vomit, you smell vomit, but if you don't have proper context cues, your own perceptions could tell you it's either. The woman who presented the seminar was French and used the microwave popcorn example (first time she smelled it, she thought it smelled like vomit), along with the example of stinky French cheese that she loves and her students think smells like stinky feet.
Vance, I don't remember seeing your post about smells. Maybe I missed it, or maybe you asked a slightly different question I couldn't answer.
It's kind of late for me here now, so I'm not going to look up any more articles tonight, but I recall from a seminar I attended that odor signals are also context-dependent. In other words, the same odorant chemicals are present in both microwave popcorn and vomit, or possibly it's the same receptors for similar chemicals (I will need to double check the details) , so if you hear the popcorn popping, you smell popcorn, and if you see vomit, you smell vomit, but if you don't have proper context cues, your own perceptions could tell you it's either. The woman who presented the seminar was French and used the microwave popcorn example (first time she smelled it, she thought it smelled like vomit), along with the example of stinky French cheese that she loves and her students think smells like stinky feet.
Vance, I don't remember seeing your post about smells. Maybe I missed it, or maybe you asked a slightly different question I couldn't answer.
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misogynisticfeminist said:
Well, the concepts of vapor pressure (of solids and liquids) is clearly relevant to the origin of smells, and diffusion describes how smells propagate.
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Phobos
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misogynisticfeminist said:
A simplification of what has already been said...
Particles or chemical fumes (i.e., very tiny particles or molecules) emitted from the smelly thing, transmitted through the air to the receptors in your nose which then send a signal to your brain which then interprets it.
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misogynisticfeminist
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hey thanks for the replies. I didn't really know that smells are so context-dependent. I was thinking something like a spectrum of smells or something, ROYGBIV-esque, with wave-lengths stuff like that. But anyway, thanks alot..
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Moonbear
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misogynisticfeminist said:
Well, in terms of the chemical that is released into the air, that's going to be the same every time, and so is the receptor in the nose that it binds to. What is different is just how we interpret the smell based on the context of our experiences. With light perception, a similar idea would be three people viewing something in the violet range of the spectrum, one says it's violet, another calls it grape and a third says it's purple. The wavelength is the same, the photoreceptors in the eye that process that wavelength is the same, it's just what the brain associates it with during processing of that information that determines what name someone would give to the color.
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Nereid
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How different are the non-mammalian smell mechanisms (from mammalian and from each other)? Do plants have a sense of smell?
If an animal has a 'keen sense of smell' (cf Homo sap.) is this principally because it has more receptors, more types of receptors, better brain wiring (e.g. lower threshold for responding to OR signals), more sensitive receptors, or something else?
If an animal has a 'keen sense of smell' (cf Homo sap.) is this principally because it has more receptors, more types of receptors, better brain wiring (e.g. lower threshold for responding to OR signals), more sensitive receptors, or something else?
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Moonbear
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Humans seem to have a pretty poor sense of smell compared to other animals. Think of how dogs can track the scent of a missing person or fugitive when humans can't detect anything. I've never looked into why this difference exists in any depth. There are a few things that may contribute. The olfactory bulbs of the brain are proportionately much larger in other mammalian species than they are in humans. Most other mammals have a far more developed accessory olfactory system as well (this seems more vestigial in humans, though there are some indications we may still detect some pheromonal signals with it, but not nearly with the same efficiency as other species)...this includes the vomeronasal organ, which is the primary sensory organ for detecting pheromonal cues in other mammals.
FAQ: Physics of Smells: Where Do They Come From?
What exactly are smells?
Smells are the result of chemical compounds in the air that stimulate our olfactory receptors, located in the nose. These receptors send signals to the brain, which interprets them as different scents.
Where do smells come from?
Smells can come from a variety of sources, including natural substances like flowers and fruits, as well as man-made substances such as perfumes and cleaning products. Some smells are also produced by chemical reactions, like when food is cooked.
How do we perceive smells?
Our olfactory receptors are able to detect thousands of different chemical compounds in the air. When these compounds bind to the receptors, they trigger electrical signals that are sent to the brain. The brain then interprets these signals as different smells based on our past experiences and memories.
Can smells affect our mood?
Yes, certain smells can have a strong impact on our mood and emotions. This is because smells are closely linked to our memories and can evoke strong emotional responses. For example, the smell of freshly baked cookies may bring back happy childhood memories, while the smell of a hospital may trigger feelings of anxiety.
How does the physics of smells relate to other scientific fields?
The physics of smells is closely related to chemistry and biology. Understanding the chemical compounds that make up different smells involves knowledge of chemical reactions and molecular structures. Additionally, our sense of smell is closely tied to our brain and nervous system, which connects to the field of neuroscience.