torpid's stupid/ignorant science questions, vol 1

[torpid]

I was washing one of my dishes today and thinking about anti-bacterial soap. Which got me to thinking about anti-biotics. Which made me confused... here's why (note I openly acknowledge the ignorance and stupidity prevalent in these questions).

1. Suppose a doctor prescribes an anti-biotic when it's unnecessary. If it's unnecessary then how can it cause mutated super germ bacteria? There are only 3 ways I can think of:

A) The person has a germ, but the germ would otherwise be killed by the immune system
B) The person has a virus only, but naturally has different germs in the body, say beneficial stomach bacteria, that somehow turns into a crazy super evil germ that is no longer good and defected to the soviet union to sell all our secrets.
C) The person will later come into contact with another germ with anti-biotics in his system and cause that germ to mutate

A seems the most logical to me. So then, how does it ever get to "super germ" status if the immune system can kill it? would it not need to evolve into both immune to amoxycillin AND immune to the immune system?

2. Can germs ever mutate to be basically immune to purell and other hand sanitizers? They say 99.99% effective. Does that 0.01% replicate and thereby turn into a super purell immune germ, or was it already immune? If there is no danger of mutation, why don't we use purell to "clean" our dishes and counter tops after handling chicken instead of soap? (That last question surely qualifies as dumbest question in this post)

3. Say you have 2 billion non-resistant bacterium in your body and 1 resistant. What prevents the 1 resistant from replicating anyway? When bacteria infest a body, do they compete for limited resources, meaning that the 1 has a greatly reduced change of survival? Thus, if you kill the 2 billion with amoxycillin, the 1 remains and has a whole chinese buffet to itself?

 

[TankGuys]

D) Person has a germ, but it's not numerous enough to cause a problem. Takes anti-biotics, kills most of them, but some live. The ones that live are now immune to the antibiotic, and should they re-produce enough to cause a problem for that person, or get passed to a new person, you now have a drug resistant bacteria.

 

[GasX]

here is an analogy:

You never see an ethiopian body builder. There may be some guy sitting on a dirt farm who is genetically the greatest bodybuilder ever but snce he has to share his bowl of rice with his 12 sisters, he never gets big and strong enough to compete. Some bird flu comes through the neighborhood and wipes out 90% of the population. Our friend now has 10X the food to eat and is soon posing on the cover of Juiced magazine.

 

[torpid]

Originally posted by: Mwilding
here is an analogy:

You never see an ethiopian body builder. There may be some guy sitting on a dirt farm who is genetically the greatest bodybuilder ever but snce he has to share his bowl of rice with his 12 sisters, he never gets big and strong enough to compete. Some bird flu comes through the neighborhood and wipes out 90% of the population. Our friend now has 10X the food to eat and is soon posing on the cover of Juiced magazine.

Where's the immune system in this analogy? It should be killing him off either way...

 

[Bryophyte]

Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

 

[imported_Tick]

Originally posted by: torpid

Originally posted by: Mwilding
here is an analogy:

You never see an ethiopian body builder. There may be some guy sitting on a dirt farm who is genetically the greatest bodybuilder ever but snce he has to share his bowl of rice with his 12 sisters, he never gets big and strong enough to compete. Some bird flu comes through the neighborhood and wipes out 90% of the population. Our friend now has 10X the food to eat and is soon posing on the cover of Juiced magazine.

Where's the immune system in this analogy? It should be killing him off either way...

There's 1000's of him, and they are constantly being killed, but they are replicating fast enough that they never all die, or death takes a long time. And they're moving to other contries too.

 

[sao123]

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

 

[Gooberlx2]

Combination of A and C.

- Not all of a particular bacterial infection will be killed when you're being treated with antibiotics, and subjecting the same strain to the same antibiotic can produce resistance mutations over time. The resistant bacteria are then selected for in a micro-evolutionary scale.
- Bacterias can come in contact with a different strain or even species and exchange DNA information (conjugation), which spreads resistance.
- Many people don't stick to their prescription and either take too little antibiotics in a day or don't continue for the full length of the prescription. When they come in contact with another bacteria they have the presence of antibiotics in their system, but not enough to kill off the infection, which takes you back to my first point.

Perhaps eventually your body will fight off the infection, but germs will escape your body anyway (sneezing, snotting, coughing, touching, etc...).

 

[torpid]

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

I understand that part, but these bacteria aren't dangerous if your immune system can fend them off, right? So they need to also be "resistant" to the immune system, meaning some sort of pretty serious illness. Take staph, for example. I've had staph infections. They don't really go away that easily. I have to apply antibiotics. So there's no reasonable way that MRSA could have been prevented, right? Because it's not really feasible to just let staph multiply disgustingly on the body.

It seems like it has to be a probability thing, if anything. Like, you are applying an unnecessary selection force to the bacteria sometimes, which might select resistant bacteria, which then could over time get selected into immune resistant bacteria...???

 

[Gooberlx2]

Originally posted by: torpid
It seems like it has to be a probability thing, if anything. Like, you are applying an unnecessary selection force to the bacteria sometimes, which might select resistant bacteria, which then could over time get selected into immune resistant bacteria...???

Pretty much, probabilities improve when you're applying the selection force to populations in the trillions.

Yes they can possibly mutate to beat your immune system....but then that's a whole different can of worms because not everyone's immune system is the same.

 

[Gooberlx2]

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

The frequency and ease of mutations at a microscopic/single-cell scale increases significantly, especially in super large populations like bacteria would be.

 

[TastesLikeChicken]

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

It's not exactly unexplained. DNA replication and transcription errors can account for some of the changes. In populations like bacteria that are large and have a high rate of reproduction such errors can result in favorable changes that provide a mode of genetic adaptation in a changing environment. Those types of changes have been well studied in populations of bacteria cultures that have been subjected to environmental stress.

 

[sao123]

Originally posted by: TastesLikeChicken

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

It's not exactly unexplained. DNA replication and transcription errors can account for some of the changes. In populations like bacteria that are large and have a high rate of reproduction such errors can result in favorable changes that provide a mode of genetic adaptation in a changing environment. Those types of changes have been well studied in populations of bacteria cultures that have been subjected to environmental stress.

The problem being thus on a larger scale...

Lets say that a liver develops a favorable change by high rate of cell reproduction (regardless of what this new trait is). how exactly would that favorable change be passed on? After the 3rd-5th percent of life is lived (this is in humans, mind you) or even .001-1% in smaller creatures, all the reproductive cells (sperm/eggs etc) are already genetically formed & complete and they will not reflect the new favorable trait... How exactly will this new trait be passed on?

There's something about natural selection which doesnt quite make sense.

 

[flashbacck]

Originally posted by: sao123

Originally posted by: TastesLikeChicken

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

It's not exactly unexplained. DNA replication and transcription errors can account for some of the changes. In populations like bacteria that are large and have a high rate of reproduction such errors can result in favorable changes that provide a mode of genetic adaptation in a changing environment. Those types of changes have been well studied in populations of bacteria cultures that have been subjected to environmental stress.

The problem being thus on a larger scale...

Lets say that a liver develops a favorable change by high rate of cell reproduction (regardless of what this new trait is). how exactly would that favorable change be passed on? After the 3rd-5th percent of life is lived (this is in humans, mind you) or even .001-1% in smaller creatures, all the reproductive cells (sperm/eggs etc) are already genetically formed & complete and they will not reflect the new favorable trait... How exactly will this new trait be passed on?

There's something about natural selection which doesnt quite make sense.

I think you misunderstand. Genetic mutations do happen during the formation of sperm/eggs. If the product of those mutant sperm/eggs have a better chance of surviving, then they have a better chance of reproducing and passing on whatever special genes they have.

 

[TastesLikeChicken]

Originally posted by: sao123

Originally posted by: TastesLikeChicken

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

It's not exactly unexplained. DNA replication and transcription errors can account for some of the changes. In populations like bacteria that are large and have a high rate of reproduction such errors can result in favorable changes that provide a mode of genetic adaptation in a changing environment. Those types of changes have been well studied in populations of bacteria cultures that have been subjected to environmental stress.

The problem being thus on a larger scale...

Lets say that a liver develops a favorable change by high rate of cell reproduction (regardless of what this new trait is). how exactly would that favorable change be passed on? After the 3rd-5th percent of life is lived (this is in humans, mind you) or even .001-1% in smaller creatures, all the reproductive cells (sperm/eggs etc) are already genetically formed & complete and they will not reflect the new favorable trait... How exactly will this new trait be passed on?

There's something about natural selection which doesnt quite make sense.

You're bringing two separate issues into play here - evolution and natural selection. While somewhat related they are not the same thing.

As to how it works in higher life forms beyond bacteria, that's also a related but entirely different issue that spans well beyond the bounds of the OP.

 

[Bill Brasky]

Originally posted by: sao123

Originally posted by: TastesLikeChicken

Originally posted by: sao123

Originally posted by: Bryophyte
Bacteria that survive the antibiotic use are selected for and become more prolific, because they are resistant to that antibiotic. The bacteria get challenged by another antibiotic, and the survivors are now culled down to those that are now resistant to two different antibiotics. And so on...

except that... evolution doesnt really explain anything

If a bacterium was exposed to chemical A (which kills bacteria)...
Then... if the bacteria isnt immune to chemical A, then it dies.
Or...if it is immune to chemical A, it was already immune, and nothing has changed.

Yes the survivng bacteria will multiply and continue its line... (which is sadly all that darwin claimed)...

but something prior to exposure must have caused that change...this is still the unexplained part of the theory...which is why most people still say it's BS.

It's not exactly unexplained. DNA replication and transcription errors can account for some of the changes. In populations like bacteria that are large and have a high rate of reproduction such errors can result in favorable changes that provide a mode of genetic adaptation in a changing environment. Those types of changes have been well studied in populations of bacteria cultures that have been subjected to environmental stress.

The problem being thus on a larger scale...

Lets say that a liver develops a favorable change by high rate of cell reproduction (regardless of what this new trait is). how exactly would that favorable change be passed on? After the 3rd-5th percent of life is lived (this is in humans, mind you) or even .001-1% in smaller creatures, all the reproductive cells (sperm/eggs etc) are already genetically formed & complete and they will not reflect the new favorable trait... How exactly will this new trait be passed on?

There's something about natural selection which doesnt quite make sense.

You are correct. In that case, the favorable liver trait will not be passed on because the mutation occurred after the germ cells differentiated. But lets say the favorable mutation occurred in a female's egg, which is then fertilized. The baby will have the mutation in all of it's cells and it can be passed on. Another possibility is that the mutation happens in the zygote before the germ cells have differentiated.

edit: ah they beat me to it.