neither are humans. We cannot make our own food. We need to steal another organisms machinery to obtain food. In this case plants No one would say plants are alive and humans are not Sent from my LG-E739 using Grasscity Forum mobile app
We don't steal any machinery.. We break it down for energy. That's metabolism and viruses don't have that either.. Viruses are literally proteins, they don't go looking for food or hosts Also, viruses require the host To pick them up and they can't search for energy to live. This goes back to the virus not being self sufficient or sustainable. I Sent from my iPhone using Grasscity Forum mobile app
By your definition a meme and ideas would be living as well Sent from my iPhone using Grasscity Forum mobile app
midnittoke hits it on the head Some viruses have very complex life cycles, but they dont require any energy. Influenza virus, for instance, has a genome of 8 seperate strands of RNA molecules. Its entrance is controlled entirely by pH differences. It steals a small chunk off the beginning of host messenger RNAs and uses that as a primer for transcription of mRNAs that can be made into protein. It even brings its own polymerase(replication machinery). It leaves by binding the same sugar it did to come in, but this time it releases because of a different surface protein. Because no energy is required and everything just happens naturally it seems obvious to me that viruses are not alive.
Except for the fact that plenty of energy IS required. Although parts of the viral life cycle are thermodynamically spontaneous, other parts, particularly genome replication, transcription, and translation do require an input of energy from the cell. That process doesn't happen "naturally" either. It's no simple feat to infect a cell. A virus needs to have the correct proteins which are different depending on the cell type and those receptors can also change due to mutations or other factors. Once inside the cell, the process of hijacking the host's machinery is also no cake walk. Viruses must do this while continually circumventing immune systems. Changing in response to external stimulus is a commonly used characteristic of life and it's one that viruses arguably do better than any other traditionally "living" organism.
Movement = kinetic energy It has to gain that energy from somewhere. Also ph gradients are a way energy is generated. Even a protein changing confirmation in response to PH is energy transfer NEXT: lets ask what the value of classifying things into the categories of living and non living is?
Yeah I meant no metabolic steps but was pretty fresh baked. And thats exactly how influenza enters the cell actually. It attaches and comes in by endocytosis and the endosome is acidified. The lower pH inside changes the conformation of a protein (hemagluttinin) shooting a hydrophobic section into the endosomal membrane. Further acidification ratchets the membranes together and releases the genome.
This sounds like sex.. But really live things are only taking from one form of energy and transferring it to another....Rocks are 'non-living' because they are inanimate objects...viruses spreading- feeding-yes-off a host- but we as humans feed off nature...as well as everything that could be thought of as 'alive'-processing shit
A virus doesn't feed on anything. It simply makes use of replication equipment. It also doesn't under go cellular division. Sent from my iPhone using Grasscity Forum mobile app
Which is why it's not characterized as "living"... Sent from my iPhone using Grasscity Forum mobile app
Viruses are to life like Pluto is to planets. Close enough to be considered, but in reality fall short of the requirements.. but like Pluto being considered a planetoid, viruses do need a category between nonliving and living.