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Here's what I don't understand... If viruses and bacteria are all over your body and do some useful things, how can some be bad? What separates 'bad' virus from

Here's what I don't understand... If viruses and bacteria are all over your body and do some useful things, how can some be bad? What separates 'bad' virus from a good virus?

JoeAltmaier 7y ago
Is that really a question? If some people are good and do useful things, how can there be murderers? { edit: explanation } Viruses are tiny fragments of dna and proteins that are only there to throw a monkey wrench into your cells. Sometimes that monkey wrench does fairly harmless things. These viruses thrive, because they find lots of healthy hosts over a long period of time. But some break things badly, reproduce out of control or change your cells' functions to be less optimal. These don't do as well, since their hosts don't thrive. The viruses don't 'care' what they're doing; they're just bits of junk that mutate a lot. The ones that kill things quickly, tend to die out. The only reason the world isn't full of horrible murdering viruses (any more than it is) is, statistics. Not some grand plan or kindly act of nature.
DoofusOfDeath 7y ago
The question seems pretty basic, but it's a good one. I realized I'm not 100% confident in the answer I was about to give. Hopefully we'll get an answer from an actual expert.
catalogia 7y ago
Some berries taste great but some berries poison you. Real puzzling isn't it.
- 7952 7y ago
  It is interesting though. Why would a plant evolve to kill animals when the purpose of a berry is to spread seed through consumption?
  - viklove 7y ago
    > purpose of a berry is to spread seed through consumption That's not the purpose of the berry. The purpose is just to ensure the survival of the seed. In drought-stricken environments, the seed is probably better off keeping its shell of water and fructose until it can form a root system.
  - MikeAmelung 7y ago
    It is pretty interesting. I think if you remember that it's just random the way things get selected for, it's a little easier to understand. It's not like the plants decided over a generation or two to start killing things. In a lot of cases, birds could eat the berries and be fine and continue to spread the plant all over.
  - s1artibartfast 7y ago
    One possible explanation is that many plants and berries which are poisonous to humans are not poisonous to other animals. For other plants it may be advantageous to be poisonous to one species and not another
  - nwallin 7y ago
    Holly berries taste delicious to birds, but are slightly toxic to mammals. (enough to cause nausea, vomiting, and diarrhea, but not to kill you) Birds don't have receptors for capsaicin, the chemical that makes chilies spicy, which makes most mammals (but not humans) not eat them. Deadly nightshade isn't toxic to birds. Birds tend to travel farther during any given time period than (typically terrestrial) mammals do, making them better at spreading seeds over a wide area. So it's evolutionarily advantageous for plants to optimize their fruits to be eaten by birds instead of mammals.
CaptArmchair 7y ago
Viruses or bacteria aren't 'bad' or 'good' in themselves. The former is arguably 'life' and the latter is a single cell organism. Free will or morality are foreign concepts as to how they behave. 'good', 'bad' or 'successful' are labels we, humans, attribute to them. Micro organisms are all about spreading genetic material, since they are so small, they have evolved passive strategies to do just that. Such as using a host organism and hitching a ride via fluid exchange. What makes all the difference is where they will end up, and how they behave in particular environments. Coronavirus outside your body is harmless, but if it gets in your lungs, it may destroy those while it replicates. Your gut teems with bacteria. There are dozens of species living in your colon. And you actually need them since they help break down food into its constituent parts in order for your gut to be able to absorb the nutrients. https://en.wikipedia.org/wiki/Human_gastrointestinal_microbiota https://en.wikipedia.org/wiki/Human_gastrointestinal_microbi... However, if your bowels get perforated and that bacterial contents seeps between your organs, you'll get in deep deep trouble: these bacteria will start to infect organs they shouldn't infect, get into your bloodstream. You'll get sepsis and risk death. So, harmless bacteria turn deadly if they end up in the wrong spot. The interesting part about viruses is that through the way they operate - injecting itself into the DNA of our cells which will then bang off new copies of the virus - their genetic material has embedded itself into our own genome. It is estimated that 5 to 8% of the human genome consists of "endogenous viral elements". These are basically viral left overs, not viruses themselves, to be clear! https://en.wikipedia.org/wiki/Endogenous_retrovirus https://en.wikipedia.org/wiki/Endogenous_retrovirus Micro organisms have been with us for a long, long time. We have evolved concurrently with them. And we will keep evolving alongside, evolving strategies - such immunity, or our ability to understand how they work - to ward off infections while new species will pop up and some might be successful in thwarting our evolved defenses.
nkohari 7y ago
Viruses can't reproduce on their own; they need to invade host cells and reprogram them to generate more virus. As potential hosts, we would consider a "bad" virus to be one that does this too aggressively, sickening or even killing the host.

Here's what I don't understand... If viruses and bacteria are all over your body and do some useful things, how can some be bad? What separates 'bad' virus from a good virus?

JoeAltmaier 7y ago

Is that really a question? If some people are good and do useful things, how can there be murderers? { edit: explanation } Viruses are tiny fragments of dna and proteins that are only there to throw a monkey wrench into your cells. Sometimes that monkey wrench does fairly harmless things. These viruses thrive, because they find lots of healthy hosts over a long period of time. But some break things badly, reproduce out of control or change your cells' functions to be less optimal. These don't do as well, since their hosts don't thrive. The viruses don't 'care' what they're doing; they're just bits of junk that mutate a lot. The ones that kill things quickly, tend to die out. The only reason the world isn't full of horrible murdering viruses (any more than it is) is, statistics. Not some grand plan or kindly act of nature.

DoofusOfDeath 7y ago

The question seems pretty basic, but it's a good one. I realized I'm not 100% confident in the answer I was about to give. Hopefully we'll get an answer from an actual expert.

catalogia 7y ago

Some berries taste great but some berries poison you. Real puzzling isn't it.

7952 7y ago
It is interesting though. Why would a plant evolve to kill animals when the purpose of a berry is to spread seed through consumption?
- viklove 7y ago
  > purpose of a berry is to spread seed through consumption That's not the purpose of the berry. The purpose is just to ensure the survival of the seed. In drought-stricken environments, the seed is probably better off keeping its shell of water and fructose until it can form a root system.
- MikeAmelung 7y ago
  It is pretty interesting. I think if you remember that it's just random the way things get selected for, it's a little easier to understand. It's not like the plants decided over a generation or two to start killing things. In a lot of cases, birds could eat the berries and be fine and continue to spread the plant all over.
- s1artibartfast 7y ago
  One possible explanation is that many plants and berries which are poisonous to humans are not poisonous to other animals. For other plants it may be advantageous to be poisonous to one species and not another
- nwallin 7y ago
  Holly berries taste delicious to birds, but are slightly toxic to mammals. (enough to cause nausea, vomiting, and diarrhea, but not to kill you) Birds don't have receptors for capsaicin, the chemical that makes chilies spicy, which makes most mammals (but not humans) not eat them. Deadly nightshade isn't toxic to birds. Birds tend to travel farther during any given time period than (typically terrestrial) mammals do, making them better at spreading seeds over a wide area. So it's evolutionarily advantageous for plants to optimize their fruits to be eaten by birds instead of mammals.

CaptArmchair 7y ago

Viruses or bacteria aren't 'bad' or 'good' in themselves. The former is arguably 'life' and the latter is a single cell organism. Free will or morality are foreign concepts as to how they behave. 'good', 'bad' or 'successful' are labels we, humans, attribute to them. Micro organisms are all about spreading genetic material, since they are so small, they have evolved passive strategies to do just that. Such as using a host organism and hitching a ride via fluid exchange. What makes all the difference is where they will end up, and how they behave in particular environments. Coronavirus outside your body is harmless, but if it gets in your lungs, it may destroy those while it replicates. Your gut teems with bacteria. There are dozens of species living in your colon. And you actually need them since they help break down food into its constituent parts in order for your gut to be able to absorb the nutrients. https://en.wikipedia.org/wiki/Human_gastrointestinal_microbiota https://en.wikipedia.org/wiki/Human_gastrointestinal_microbi... However, if your bowels get perforated and that bacterial contents seeps between your organs, you'll get in deep deep trouble: these bacteria will start to infect organs they shouldn't infect, get into your bloodstream. You'll get sepsis and risk death. So, harmless bacteria turn deadly if they end up in the wrong spot. The interesting part about viruses is that through the way they operate - injecting itself into the DNA of our cells which will then bang off new copies of the virus - their genetic material has embedded itself into our own genome. It is estimated that 5 to 8% of the human genome consists of "endogenous viral elements". These are basically viral left overs, not viruses themselves, to be clear! https://en.wikipedia.org/wiki/Endogenous_retrovirus https://en.wikipedia.org/wiki/Endogenous_retrovirus Micro organisms have been with us for a long, long time. We have evolved concurrently with them. And we will keep evolving alongside, evolving strategies - such immunity, or our ability to understand how they work - to ward off infections while new species will pop up and some might be successful in thwarting our evolved defenses.

nkohari 7y ago

Viruses can't reproduce on their own; they need to invade host cells and reprogram them to generate more virus. As potential hosts, we would consider a "bad" virus to be one that does this too aggressively, sickening or even killing the host.