Survival

[Kumar]

Bolding mine.

You're attributing sentience and/or planning ability to individual cells, why? [/qoute]

Sorry I couldn't understand it. Will you simplyfy for me?

Also, cancer cells can be immortal given the right conditions. HeLa cells are cancer cells that can divide an unlimited number of times, provided they are supplied with nutrients (usually on a petri dish). The reason cancer cells in the body eventually die is that they kill the host, cutting off their supply of nutrients.

Cancer cells do not "know" that they're killing their host, they just divide and divide as long as there are the raw materials for them to do so. It's what they do.

Probably such immortality kill them along with their parent.

As I asked in my last post,

To be more precise, does it mean that cancer cells are either mad or self destructive?

Btw in view of their immortality, is it necessary that cancer should start in stem cells?

 

[MRC_Hans]

Do pathogens send their next generations to other host even at their cost?

That is possible, yes. We also see in higher life-forms that parents sacrifice themselves to ensure the next generation.

You see, evolution favors the survival of the species (of the gene, in fact), not the individual.

As for pathogens and other parasites, parasitism is simply failed symbiosis.

Hans

 

[Kumar]

To my knowledge, cancer cells don't need to live long as long as they reproduce at a fast rate, which they do.

I believe that the timespan a cancer cell lives is perfectly sufficient for the cell itself. Being a cell, it won't really gain anything from living longer, would it?

It is a big question.

If cancer cell don't need, gain or want to live long, why it want to replicate?

 

[MRC_Hans]

To be more precise, does it mean that cancer cells are either mad or self destructive?

The terms 'mad' and 'self-destructive' imply intelligence and intent. Cancer cells (and other cells, for that matter) are neither intelligent nor have they intent. They are essentially delicate mechanisms working in the way they are programmed to work. In cancer cells, the program is bugged.

Btw in view of their immortality, is it necessary that cancer should start in stem cells?

No.

Hans

 

[MRC_Hans]

It is a big question.

If cancer cell don't need, gain or want to live long, why it want to replicate?

Kumar, READ the answers, for god's sake! Cancer cells don't WANT anything. They function the way their internal program forces them to function.

Hans

 

[Lukraak_Sisser]

They don't *want* to replicate. They dont want anything. They are cells, and cells are not sentient in any way.
Multicellular organisms exist because they have mechanisms in control to prevent the cells from acting like single celled organisms allowing for cooperation. But these mechanisms are not perfect and can break down. At which point the cells start replicating without restraint and eventually kill the organism they were a part of.

Pathogens are different, they use their host organisms as both food source and transmissiona agent. The most succesful ones don't actually kill their host (normal flu for instance), but even the ones that kill are succesful enough to continue existing, so they are doing something right.

 

[Kumar]

Most very harmful pathogens are either "new", can survive outside a human host (in animals where they do less harm, in water, etc.), are harmless or less harmful in some people (carriers), or can spread before their effects become apparent. Diseases that require time and possibly the appearance of health in a human host in order to spread effectively will tend to evolve to become less virulent (at least initially), as has apparently happened to many common diseases.

One confusion is there;

Spread or live long. I don't think their spreading to other host justify their intention to live long? Are they spreading or transfering to new host by leaving previous host which probably become weaker?

 

[Kumar]

On the cancer cells, I don't think so. My understanding of cancer is it's a condition where the cells simply don't check themselves and just keep multiplying uncontrolled. To put it simply they don't know any better.

Of course this is personifying. "They" don't know to stop growing and not kill the host any more than say the road knows to get out of the way of a car and not get worn down, or a river to change direction to prevent from becoming a lake.

Simply, they are either mad or self destructive?

As for pathogens they are unique, some do require the death of the host to survive.

How they can survive if ther require death of host?

Others don't and their life cycle is more like a parasite, they require the host surviving for their own survival. At least that's my understanding.

I think you aren't looking at the big picture. It seems to me the majority of pathogens, the majority of the time, don't kill the host. It's only a few them that do and even then it's not intentional.

Then they are not so bad. They may not kill but still they do some harm to host, obiously host do not benefit from it.

 

[Furcifer]

One confusion is there;

Spread or live long. I don't think their spreading to other host justify their intention to live long? Are they spreading or transfering to new host by leaving previous host which probably become weaker?

Stronger, the presence of antigens makes them stronger in the long run. Antigens also make transmission necessary.

 

[Furcifer]

Simply, they are either mad or self destructive?

Mad I suppose.

More like a car with a brick on the gas pedal, cancer being the brick causing the car to speed out of control.

How they can survive if ther require death of host?

I seem to recall pathogens that can kill the host then multiply in the dead organism before becoming airborn. Or maybe it was a Sunday afternoon movie...

Then they are not so bad. They may not kill but still they do some harm to host, obiously host do not benefit from it.

I think there are specific pathogens that produce antigens in the host which make them immune to a variety of other pathogens. That's a benefit in some cases.

 

[MRC_Hans]

One confusion is there;

Spread or live long. I don't think their spreading to other host justify their intention to live long? Are they spreading or transfering to new host by leaving previous host which probably become weaker?

Kumar, I think it is very insulting that you ask questions and ignore the answers.

They have no intention. They are cells. Pahogens are simply cells (vira are not even that). And they have no evolutionary reason to live long, only to spread.

Now, do try to understand it.

Hans

 

[Kumar]

That is possible, yes. We also see in higher life-forms that parents sacrifice themselves to ensure the next generation.

It it natural but probably decreasing in us.

You see, evolution favors the survival of the species (of the gene, in fact), not the individual.

As for pathogens and other parasites, parasitism is simply failed symbiosis.

Hans

Following quote should have some relevance to this topic so quoting.

Symbiosis is a close ecological relationship between the individuals of two (or more) different species. Sometimes a symbiotic relationship benefits both species, sometimes one species benefits at the other's expense, and in other cases neither species benefits.

Ecologists use a different term for each type of symbiotic relationship:

Mutualism -- both species benefit
Commensalism -- one species benefits, the other is unaffected
Parasitism -- one species benefits, the other is harmed
Competition -- neither species benefits
Neutralism -- both species are unaffected
http://www.cals.ncsu.edu/course/ent591k/symbiosis.html

Yes we don't have Symbiosis relationship with cancer cells.

Whether pathogens come into above categories?

 

[MRC_Hans]

Simply, they are either mad or self destructive?

IT HAS BEEN ANSWERED! Read the answers before you ask again, or you make a complete fool of yourself.

They are not mad, they are defective.



Hans

 

[Kumar]

Kumar, I think it is very insulting that you ask questions and ignore the answers.

They have no intention. They are cells. Pahogens are simply cells (vira are not even that). And they have no evolutionary reason to live long, only to spread.

Now, do try to understand it.

Hans

Sorry don't take it otherway. I respect & care all. But just language difference. Therefore I prefer to quote instead to write.

Thanks. They are quite sacrificing & generous to their daughter cells.

 

[Kumar]

great , fire away..


may i just add/edit your phrase here?

Every/most live being/s would like attempts to live long, enough....

"enough for what?" one may ask then, and the answer is long enough to breed. Longevity of life span itself without reproduction for organisms that reproduce is not a survival trait.


Suvival means, in terms of evolution, evolution and survival of the species, not any particular individual in that species. no breeding = no species essentially.

not the individual's survival, as a single unit, no, its more like
"behave & evolve for his/her " decendants better survival.


Fit meaning "fit enough to reproduce" not fit enough to live to a hundred years or run the fastest.

Yes thanks for correction & information. I could learn here difference between survival & live long. These cells are quite sacrificing generous to their daughter cells.


Because if the exisiting ones you can see today survived from host to host, then they lived long enough.

Look at the amazing variety of organisms lifespan lengths on the planet.
Those species obviously bred enough to get this far, and it worked.

(if it didn't , they died out and aren't here)[/quote]

Right. They are quite far-sighted.

also "pathogens and cancer" is not a way I'd approach this.

They are small words for a big subject........

www.cancerhelp.org.uk/cells

http://en.wikipedia.org/wiki/Pathogen

I can see what you are on about I think, but an infected host for example would only need to be alive long enough for the organism to breed to other hosts really.

You may yourself consider there to be an advantage to the host living longer, but longer life span of itself and by itself is not a species survival trait, however breeding is.





And you, do you see here what i mean?

Yes, you made it simple to me and I feel/fing that truth is simple.

 

[Kumar]

Kumar, viruses are not sentient. They just do what they do.

Do you mean that neither virus nor cancer cells have consiousness/mind?

 

[Kumar]

The terms 'mad' and 'self-destructive' imply intelligence and intent. Cancer cells (and other cells, for that matter) are neither intelligent nor have they intent. They are essentially delicate mechanisms working in the way they are programmed to work. In cancer cells, the program is bugged.


No.

Hans

Didn't cancer cells got communications from body before they became cancerous? Don't they get & follow any body signals on becoming cancerous?

 

[MRC_Hans]

Yes we don't have Symbiosis relationship with cancer cells.

Cancer cells are neither parasitic nor symbiotic, they are US. They are a malfuctioning part of us.

Whether pathogens come into above categories?

'Pathogen' means 'disease giver' so no, they are not symbiotic, they are parasitic. However, we have plenty of symbiotic micro organisms. You have a pound or so of bacteria in your intestines, they help you digest your food, and you feed them in return.

Hans

 

[Naddig74]

Do you mean that neither virus nor cancer cells have consiousness/mind?

Of course they don't. You are making some basic errors of assumption about what viruses, bacteria, cancer cells etc are.

They don't think, or have any conscious intention. They just do what their DNA tells them to do...reproduce.

 

[Kumar]

Kumar, READ the answers, for god's sake! Cancer cells don't WANT anything. They function the way their internal program forces them to function.

Hans

Sorry, as I got many awnsers, I was going one by one.

As I asked, does it mean that they don't communicate with body & nature in any way?