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2006-06-21 04:18:40 · 17 answers · asked by Noncyclicphotophosphorylation 2 in Science & Mathematics Biology

17 answers

Non-living. It cannot reproduce by itself, cannot regulate homeostasis, depends/hijacks other hosts for reproduction. It's mostly leftover/waste DNA of some bacteria/protist that ejects their DNA into the air with a protein capsule to reproduce, although this didn't work.

2006-06-21 04:21:25 · answer #1 · answered by Anonymous · 0 0

2

2016-08-29 03:19:01 · answer #2 · answered by ? 3 · 0 0

Non-living.

2006-06-21 04:28:09 · answer #3 · answered by songbird 6 · 0 0

A virus is just a sack of DNA that infects healthy cells and forces them to makes copies of the nasty DNA. Think of viruses as land mines and bacteria like enemy soldiers: both will kill you, but you can only kill the bacteria. So no, virus are not living organisms.

2006-06-21 04:25:37 · answer #4 · answered by slurpeeman86 1 · 0 0

a virus is a living organism

2006-06-21 04:21:57 · answer #5 · answered by JoJo 2 · 0 0

Viron: transmissible state of a virus. These structures contain a nucleic acid core wrapped in a protein coat. This coat is called a capsid. Some virons contain an envelope, constructed from the host cell membrane. The nucleic acid core may be DNA ( double strand, single strand), or RNA ( single strand, double strand), but never both. The shape of these virons vary from spherical, cylindrical, bullet-shaped , to amorphous shaped particles. They vary in diameter from 18 to 300 nm. Virons must infect a living cell. Viruses are obligate intracellular parasites. Some virons are hardier than others ( hepatitis virus can withstand short periods of boiling; most virons are destroyed by this).

Viral Replication: most viruses carry the enzyme RNA replicase to make complementary RNA strands. Some viruses contain the enzyme reverse transcriptase, which produces DNA , then RNA. These are called retro viruses. HIV is an example of a retro virus. The three basic patterns of genome replication are: DNA--->DNA, RNA---->RNA, and RNA------->DNA---->RNA. Viral components are held together by weak bond (van der Waals forces and hydrogen bonds).
Host Specificity: Each type of virus can infect and parasitize a limited range of host cells. They are guided by external recognition areas of the host cell. This may keep a virus from infecting many different types of cells.

Lytic Cycle: Life cycle of virulent phages.

1. The phage lands on the host cell, and using 140 ATP's in its tail fibers, injects its nucleic acid core into the bacterium.

2. The host's DNA is cut up and destroyed by the enzymes produced by the host from the new DNA.

3. The now unassembled nucleotides are reassembles into phage DNA, which produces copies of the capsid.

4. The genes also produce the enzyme lysozyme, that digests the bacterial cell wall, causing the newly assembled viruses to escape.

Lysogenic Cycle: Viruses that reproduce without killing their hosts are called temperate viruses. These viruses have 2 alternate forms of reproduction. The lytic cycle or the lysogenic cycle. The process begins very similar to the lytic infection or inserting the genome into the host's genome and becoming dormant. During the lysogenic cycle one of the temperate phage's genes remains active. It codes for a repressor protein keeping the prophage genes inactive. From here on the cells reproduce regularly. Each carrying the hidden genes of the virus. Under normal circumstances harmless bacteria remain so until infected by these viruses; then they can become pathogenic. Example Botulism, diphtheria, and scarlet fever bacteria.
Diseases caused by viruses: small pox, chicken pox, cold sores, herpes, Rubella, yellow fever, AIDS, rabies, mumps, influenza, measles,and some forms of cancer.

2006-06-28 02:24:59 · answer #6 · answered by ATP-Man 7 · 0 0

Any of various simple submicroscopic parasites of plants, animals, and bacteria that often cause disease and that consist essentially of a core of RNA or DNA surrounded by a protein coat. Unable to replicate without a host cell, viruses are typically not considered living organisms.

2006-06-21 13:28:45 · answer #7 · answered by Professor Armitage 7 · 0 0

virus is non living its a program

2006-06-21 04:23:38 · answer #8 · answered by sankalp 2 · 0 0

This is a tricky question because you first need to define if virus is a living thing. Virus doesn't have all the characteristics we learn regarding living thing.............so..................

2006-06-21 04:24:42 · answer #9 · answered by criswcliu 2 · 0 0

Viruses are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, which are living organisms, viruses are not truly alive.

2006-06-21 04:24:23 · answer #10 · answered by bjm_116 2 · 0 0

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