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234

Apparently you're not the first person to notice this; in 1895, a German nose specialist called Richard Kayser found that we have tissue called erectile tissue in our noses (yes, it is very similar to the tissue found in a penis). This tissue swells in one nostril and shrinks in the other, creating an open airway via only one nostril. What's more, he found ...


127

This is a natural phenomenon called the nasal cycle. It is discussed in this paper by Telles et al. (1994), among many others. The nostrils are used on an alternating cycle of about 2-3 hours, controlled by the autonomic nervous system. If you notice alternating congestion, that also seems to be coupled to the nasal cycle (Hasegawa and Kern 1977, 1978). ...


34

As others have said, this phenomena is called the nasal cycle, a process controlled by the autonomic nervous system that alternants congestion between your nostrils. Mentalfloss of all places has an article about this that explains: ...it makes our sense of smell more complete. Different scent molecules degrade at different rates, and our scent ...


16

Yes, it can, but it is extremely rare. ... nosebleeds are rarely fatal, accounting for only 4 of the 2.4 million deaths in the U.S. in 1999 [1]. The main issue is that epistaxis can be a sign of potentially fatal diseases: The instances in which nosebleed is potentially fatal are those in which there is a history of recent head injury, severe ...


6

Any injury, that results in external bleeding can lead to death, since it is a breach in the body's defenses and an entry point for pathogens. Explanation: When you have nose bleeding the blood must be coming from somewhere. Usually from inside your body. That means there is a hole in your body which is big enough for blood to stream out. That in return ...


4

The reason that cartilage rarely is able to regenerate is that it is poorly vascularized and innervated. It doesn't have its own blood supply to deliver signaling molecules that promote regeneration and repair after injury. There has been some recent progress on getting the body to repair and replace cartilage with lab created biogels detailed here.


4

Senses in general adapt to continuous stimulation due to various processes. One such process is simply the exhaustion of the reserves of a receptor, or secondary neuron, due to a depletion of neurotransmitters. Entering a room activates a fresh pool of chemical receptors, thereby generating a clear sense of smell. However, this dims due to adaptation. ...


4

The sinuses connect the ear, nose and throat as well as the tear ducts of the eye. The pressure created when holding your nose and blowing is transferred to any area it can get to; in this case, the eyes and ears.


3

It appears that little is known regarding how water is detected in mammalian mouth and throat. However, a recent study published in Nature Neuroscience(1) showed that acid-sensing taste receptor cells (TRC) participate in taste responses to water. First, the team screened knock-out mice in order to identify which TRC were involved: They used genetic ...


3

It is possible for a substance to not smell very much, but to taste very strongly - chili peppers are a great example. They (in my experience) have a rather weak spicy odor, but the taste is much much more intense. In the case of soaps, very small amounts of essential oils are used to give soaps their odors. You may be able to slightly taste them were you to ...


3

Why did it evolve ? Mammals with rhinaria tend to have more acute olfaction, and the loss of the rhinarium in the haplorrhine primates is related to their decreased reliance on olfaction, being associated with other derived characteristics such as a reduced number of turbinates. The rhinarium is very useful to animals with good sense of smell ...


2

Mostly, what you're smelling are volatile small molecules: stuff like butyrate, indole, mercaptans, hydrogen sulfide, etc. These molecules are thousands of times smaller than even the smallest pathogens, being measured in Angstrom vs. nanometer scales. Pathogens are just too large to be actually volatile, in the sense of freely escaping into the air. And ...


2

Menthol is stimulating action potential at cells which are inducing thermoception. As far as I have found out it does not have any effect beyond that. The patients only feel like they can breath better while it could not be proven that they actual do. https://www.ncbi.nlm.nih.gov/m/pubmed/18702906/ The blood vessel thing : In general "cold" is a cause for ...


1

Certain vitamins, for example, vitamin B12, can be absorbed through the nasal mucosa by simple diffusion. Many nutrients can be absorbed through the intestinal mucosa only by the help of specific carriers. These carriers are not likely present in nasal mucosa, so the nutrients in question may not be absorbed there. The other problem, especially with ...


1

Between the eyes and nose, which offers better immune protection Neither. Both are mucous membranes lined by epithelial cells. Each is their own niche (and the nose has a number of sub-niches), with particular receptors, environmental factors, and immune factors that interact with pathogen factors. The interaction between the two produces the tissue tropism ...


1

Nose bleeding (or epistaxis, as Graham rightly termed it) is common to many species, such as dogs, cats, pigs, and many other animals. As for the causes, like Graham pointed out, it really varies from species to species. To take dogs for an example, the leading causes of spontaneous nose bleeding are leishmaniasis (a tropical / subtropical disease ...


1

Cats, dogs and other animals can suffer from epistaxis. The causes differ depending on the animal. foreign things in the nose, abscess, cancerous growth, snake bite, some poisonings and diseases especially in the trachea and lungs and anthrax. Sometimes excessive sneezing or coughing can result in nose bleeding as well. All animals are susceptible to get ...


1

The vast majority of bloody noses in healthy individuals arise from one specific area in the nose (on either side): Kiesselbach's plexus. In the mucosa of the nasal septum (the cartilagenous structure separating the nose into two sides), there is an area where several arteries "meet", giving it an exceptionally rich vascular supply, called Kiesselbach's ...


1

TL; DR Mostly no. On a molecular basis, cats' and dogs' noses look quite similar to ours. Most of what we know about smell comes from studies on non-human mammals, and is supposed to apply to humans too. So, big similarity, but... Cats and dogs distinguish far more kinds of than humans. It's likely they know more kinds of bad smells and good smells, ...


1

The problem with odors is that no known odorant hits only one olfactory receptor. A saturating concentration of compound X for receptor A might be saturating another receptor B, but not receptor C. If you now decrease the concentration, receptor A is still saturated, receptor B is only partially activated and receptor C is not activated at all. Since smell ...


1

Chloride (Cl2) carries 34 protons and electrons. A common example of a relatively heavy odorless gas is CO2, carrying 22 protons and electrons. All noble gases are odorless. The heaviest, naturally occurring noble gas is Radon, which has a proton count of 86. Ununoctium, an exotic artificial element with atomic number 118, is a noble gas too. However, ...


1

The odds are that you're noticing the equality of patent nostrils in the middle of a changeover, when both are equally patent. Also, the shape of your nose may be permitting the congested side to still be fairly patent. Your nose is doing what it's supposed to be doing (and everybody suffers bilateral congestion during colds, allergies, etc.) If it were not, ...


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