what is a virus and why are they not placed in one of the animal kingdoms?

Answer 1

Do any of you actually ever talk to virologists before you throw your unsupported statements out here? c'mon.

Most virologists DO support the idea that viruses are living. Here's why:

There are 7 characteristics of life: homeostasis, organization, metabolism, growth, adaptation, response to stimuli, and reproduction.

Homeostasis - many bacteria don't maintain a stable internal environment, are they dead?

Organization - Viruses are organized, have you ever seen a crystal structure of a virion?

Metabolism - agreed, no

Growth - yes virus particles grow and mature in the host cell

adaptation (evolution) - very much yes

response to stimuli - Viruses respond to stimuli, just not the stimuli you think of naturally. Viruses modulate their reproduction and life cycles based on the "stimuli" in the host cell

Reproduction - Of course yes. Of course they reproduce and pass on their genes. And nearly all viruses encode their own replication proteins. We can even make viruses reproduce their RNA in vitro, outside the host cell.

So the only characteristic that viruses fail to qualifiy as alive for is metabolism, and it could easily be argued that metabolism is the least important and most arbitrary characteristic of living organisms since viruses do a fine job of gathering energy from their environment (host cell). Some folks can't get over this arbitrary criteria so they refuse to give the idea any thought.

There are plenty of bacteria and fungi that are obligate parasites, meaning they can't grow or reproduce outside of their hosts. Are they any less alive? I won't even begin to go into all the forms of life that don't breathe, eat, drink or "reproduce babies".

Answer 2

Ah, the ever-changing solutions :) you have become the "fundamentals" yet we've now have been given superkingdoms, and a few human beings destroy this down into purely 3 kingdoms. For classification (regardless of the actuality that for plant life, replace Phylum with branch), you have Kingdom, Phylum, classification, Order, kinfolk, Genus, Species. The mnemonic for that's linked under. There are 5 substantial kingdoms we comprehend as we communicate. some are common. plant life, animals, fungus, staggering? yet bacteria have their very own kingdom, too ; Monera. and then there are Protists. they have a nucleus, basically like the plant, animal, and fungus kingdom, yet they are not plant life, or animals, or fungus. They do seem lots like the organisms that stepped forward into plant life, animals, and fungi, and the ancestors of plant life, animals, and fungi have been protists. Seaweed, which isn't a plant in any respect (regardless of the actuality that the eco-friendly ones are appropriate, there are additionally yellow ones, crimson ones, brown ones, and blue-eco-friendly ones!) is often Protist, different than for the very few actual plant life that stay underwater. Given this, use your e book to respond to 3 to 11. each and every of those kingdoms is relatively diverse from the others! and those are the kingdoms of residing organisms, ones that are made up of cells or that are cells. Is an endemic a cellular? No. Is it a stay? no longer technically, no. So how can this is arranged with residing organisms? it would be like attempting to place a bicycle in a kingdom for residing organisms; it basically would not in high quality condition!

Answer 3

A virus contains a protein coat and has DNA strands. When a virus infects a host, it injects it's DNA into the host. It is not considered alive or in the animal kingdom because viruses don't reproduce.

Answer 4

A virus is not living. It is not placed into any of the kingdoms because of this fact. They do not require food, air, and they do not reproduce. They repilcate. They encode themselves into the DNA and RNA of the cell that they "infect" and turn that host organism into a virus making factory, basically. The host cell then only knows to make more of what is on it's DNA/RNA (viruses). It's a difficult thing to wrap your head around, I know, but that is how it works.

Answer 5

A virus is a microscopic particle (ranging in size from 20 - 300 nm) that can infect the cells of a biological organism.

It has been argued extensively whether viruses are living organisms. Most virologists consider them non-living, as they do not meet all the criteria of the generally accepted definition of life. They are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, viruses are generally not considered to be true living organisms. A definitive answer is still elusive. Some organisms considered to be living exhibit characteristics of both living and non-living particles, as viruses do. For those who consider viruses living, viruses are an exception to the cell theory proposed by Theodor Schwann, as viruses are not made up of cells.

Answer 6

Good question. On its own a virus is just a chunk of genetic material, a thousandth of the size of a bacterial cell. It cannot reproduce without tapping in to the machinery of a living host cell. Experts differ over whether to regard viruses as living or non-living, the truth is that they are somewhere inbetween.

Answer 7

viruses are lifeless. They do not eat, they do not drink, do not breath and do not reproduce babies. They look like table salt and they do not die a natural death.

The only thing they can do is to duplicate themselves in a host cell. They are just a piece of DNA, essentially a chemical substance. So they do not fit into the animal kingdom.

Answer 8

A virus is basically a piece of DNA or RNA wrapped in a protein coat.

Viruses are not considered a form of "life" because, while they do replicate, they do not *self*-replicate. They require the reproduction machinery of a host cell to replicate.

Answer 9

I assume you meant why are viruses not in one of the top-level taxons. There is only one animal kingdom.

Nonetheless, viruses are not self-replicating and require a host cell to replicate thus they are considered to be proto-organisms

Answer 10

it is the smallest infectious micro organisms
they do not contain enzymes for metabolism