How does natural selection determine which mutations remain and which do not?

[xianghua]

1. One of the structures arose by itself, and maintained the function as recognized currently, albeit it wasn't nearly as good at it, and the other two originated as beneficial but not necessary accessory structures. Over time, as they all became more specialized, the former accessory structures became an absolutely necessary part of the system. I already mentioned this one in a previous post.

ok. but since currently an olfactoryre ceptor by itself is meaningless, there is no evidence to back up this possibility.

2. All the structures had different original functions, and the currently recognized primary function was originally a secondary function of these structures that became more developed over time. After all, structures can have more than one function at a time.

i dont think it's possible too. you can tets it with your cell-phone. if you will remove your battery you will get non-functional cell phone and not somehing else.

 

[pitabread]

if you will remove your battery you will get non-functional cell phone and not somehing else.

Sure you will. With our older, non-functional cell phones, we gave 'em to my nieces. What once was a communication device, was now a toy phone that they played with.

 

[PsychoSarah]

ok. but since currently an olfactoryre ceptor by itself is meaningless, there is no evidence to back up this possibility.

Correction, a MODERN olfactory receptor by itself doesn't do anything, although plenty of the necessary structures that need to be present for one to function do have plenty of other, unrelated functions themselves (such as the other nerves that interpret the signals the olfactory receptor gives off in response to chemical stimuli). Also, you say that as if structures have suddenly stopped developing, which they haven't.

i dont think it's possible too. you can tets it with your cell-phone. if you will remove your battery you will get non-functional cell phone and not somehing else.

If I remove the battery and plug in the charger, it can still work silly. When I had my old, terrible HP computer, I had to do that a lot to keep it from overheating. Also, you are comparing things we design with nature again. Bad xianghua, how many times do I have to explain the flaws in doing that? You'd actually be amazed at how much you can remove from some animals before they will actually die...

Also, are you seriously telling me you don't think structures can have more than one function at a time? Do you not know how many functions your liver has?

 

[xianghua]

If I remove the battery and plug in the charger, it can still work silly.

so you need also a charger to make it work. so you just replace one part in another= the same result.

 

[tas8831]

ok. but since currently an olfactoryre ceptor by itself is meaningless, there is no evidence to back up this possibility.

You write as if you think "olfactory receptor" is some kind of cell that is "designed" to smell things or something.

I asked a while back if you knew what kind of receptor an olfactory receptor is, and you (amazingly) did not respond.

So I will tell you - it is a chemoreceptor.

Chemoreceptors are cells with receptors on their surface that can bind chemicals, and this binding has the ability to produce, ultimately, action potentials.

IOW, olfactory receptors just detect chemicals, like many other chemoreceptors.


What you are doing with line of 'argumentation' is akin to carrying on about the invention of the tires on your Ford Fiesta, all the while ignoring that all kinds of cars and other vehicles have had tires for more than a century.

 

[PsychoSarah]

so you need also a charger to make it work. so you just replace one part in another= the same result.

Yeah, but also consider the fact that I can plug it in while it still has the battery inside, then remove the battery, and at no instance have my phone turn off.

 

[xianghua]

You write as if you think "olfactory receptor" is some kind of cell that is "designed" to smell things or something.

as far as i aware olfactory receptor is the only kind of re ceptor that can bind odor molecule.

 

[tas8831]

as far as i aware olfactory receptor is the only kind of re ceptor that can bind odor molecule.

And what, exactly, is an "odor molecule" but (usually) an organic compound?

Furans are common odorants - can we taste them?

YES.


Olfactory and taste receptors are under the umbrella classification of chemoreceptors.

 

[PsychoSarah]

as far as i aware olfactory receptor is the only kind of re ceptor that can bind odor molecule.

Nope, because all "odor molecules" are chemicals, and chemicals can be detected by any chemoreceptor that has a spot on its surface for the chemical to bond to long enough to trigger a response. Olfactory receptors are just doing what tons of different cells can do in a very specialized way (want to put in a counter to a common myth; each olfactory receptor does not respond to only 1 chemical, but actually a broad range of chemically similar molecules, and these are not unique to just 1 olfactory receptor. That is, a particular chemical could be capable of bonding to a few different olfactory receptors, with varying affinity).

 

[xianghua]

Nope, because all "odor molecules" are chemicals, and chemicals can be detected by any chemoreceptor that has a spot on its surface for the chemical to bond to long enough to trigger a response.

nope, because those olfactory receptors are specific to odor molecule. so not every kind of receptor can bind an odor molecule. are you saying that a photoreceptor can bind an odor molecule too?

 

[Speedwell]

nope, because those olfactory receptors are specific to odor molecule. so not every kind of receptor can bind an odor molecule. are you saying that a photoreceptor can bind an odor molecule too?

Did you not read the previous post? A photoreceptor is not a chemoreceptor.

And, there is no such thing as an "odor molecule" Just molecules and various types of chemorecptors to detect them.

 

[xianghua]

Did you not read the previous post? A photoreceptor is not a chemoreceptor.
.

and not every chemoreceptor is able to detect an odor molecule too:

"that can activate a nearby nerve fiber if the chemosensor is a specialized sensory receptor cell, such as the taste receptor in a taste bud[2][3] or in an internal peripheral chemoreceptor such as the carotid body"

Chemoreceptor - Wikipedia

as i said: an olfactory receptor is a special kind of receptor and not every receptor is able to bind an odor molecule.

 

[Speedwell]

and not every chemoreceptor is able to detect an odor molecule too:

"that can activate a nearby nerve fiber if the chemosensor is a specialized sensory receptor cell, such as the taste receptor in a taste bud[2][3] or in an internal peripheral chemoreceptor such as the carotid body"

Chemoreceptor - Wikipedia

as i said: an olfactory receptor is a special kind of receptor and not every receptor is able to bind an odor molecule.

You have yet to tell us what you think an "odor molecule" is. In any case, since not all chemoreceptors will detect all molecules, you will need to demonstrate that there is a qualitative difference between chemoreceptors which detect different molecules.

 

[Motherofkittens]

You have yet to tell us what you think an "odor molecule" is. In any case, since not all chemoreceptors will detect all
molecules, you will need to demonstrate that there is a qualitative difference between chemoreceptors which detect different molecules.

My thread is finally open! When I went to check on it last it was locked. Who is tto blame? I didn't want to read anything eariler because I wouldn't be able to comment. I will now after work. I noticed this thread is several pages shorter now. Please be civil.

 

[PsychoSarah]

and not every chemoreceptor is able to detect an odor molecule too:

as i said: an olfactory receptor is a special kind of receptor and not every receptor is able to bind an odor molecule.

-_- dude, the molecules that activate olfactory receptors are just regular molecules that are in the air. When you smell bleach, there are actually molecules from that solution going into your nose (this is also why smelling high concentrations of certain substances will make you feel sick; not all the molecules you have olfactory receptors for are benign).

Also, no duh not every chemoreceptor can detect all of the same chemicals. However, plenty of them do have overlap. Ethanol has a noticeable smell (olfactory receptor), as well as a taste (taste buds are also chemoreceptors) and there are chemoreceptors inside of your body that will detect its presence if you drink any, and stimulate processes that help break down that toxin. You just don't consciously feel stimulation from most of your chemoreceptors. Furthermore, every cell in the human body will have a response to numerous chemicals, most just don't interact with the nervous system to send off that information to the brain.

 

[xianghua]

-_- dude, the molecules that activate olfactory receptors are just regular molecules that are in the air. When you smell bleach, there are actually molecules from that solution going into your nose (this is also why smelling high concentrations of certain substances will make you feel sick; not all the molecules you have olfactory receptors for are benign).

Also, no duh not every chemoreceptor can detect all of the same chemicals. However, plenty of them do have overlap. Ethanol has a noticeable smell (olfactory receptor), as well as a taste (taste buds are also chemoreceptors) and there are chemoreceptors inside of your body that will detect its presence if you drink any, and stimulate processes that help break down that toxin. You just don't consciously feel stimulation from most of your chemoreceptors. Furthermore, every cell in the human body will have a response to numerous chemicals, most just don't interact with the nervous system to send off that information to the brain.

and yet: we will need a new mutation in moving to olfactory receptor from non olfactory receptor.

 

[PsychoSarah]

and yet: we will need a new mutation from moving to olfactory receptor from non olfactory receptor.

Relevance? You say that as if, in other organisms, a simpler sense of smell doesn't exist that has less specialized cells.

 

[xianghua]

Relevance? You say that as if, in other organisms, a simpler sense of smell doesn't exist that has less specialized cells.

its means that the for the first OR we will need new mutations.

 

[PsychoSarah]

its means that the for the first OR we will need new mutations.

New mutations happen all the time, so again, relevance?

 

[tas8831]

nope, because those olfactory receptors are specific to odor molecule. so not every kind of receptor can bind an odor molecule. are you saying that a photoreceptor can bind an odor molecule too?

Amazing...