20 Facts About Viruses

1.

Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.

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2.

Viruses are considered by some biologists to be a life form, because they carry genetic material, reproduce, and evolve through natural selection, although they lack the key characteristics, such as cell structure, that are generally considered necessary criteria for defining life.

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3.

Viruses are found wherever there is life and have probably existed since living cells first evolved.

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4.

Viruses are now recognised as ancient and as having origins that pre-date the divergence of life into the three domains.

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5.

Viruses do not have their own metabolism and require a host cell to make new products.

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6.

Viruses can have a lipid "envelope" derived from the host cell membrane.

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7.

Release – Viruses can be released from the host cell by lysis, a process that kills the cell by bursting its membrane and cell wall if present: this is a feature of many bacterial and some animal viruses.

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8.

Viruses are by far the most abundant biological entities on Earth and they outnumber all the others put together.

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9.

Viruses were grouped according to their shared properties and the type of nucleic acid forming their genomes.

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10.

Viruses must generate mRNAs from their genomes to produce proteins and replicate themselves, but different mechanisms are used to achieve this in each virus family.

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11.

Viruses have different mechanisms by which they produce disease in an organism, which depends largely on the viral species.

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12.

Viruses are an established cause of cancer in humans and other species.

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13.

Viruses accepted to cause human cancers include some genotypes of human papillomavirus, hepatitis B virus, hepatitis C virus, Epstein–Barr virus, Kaposi's sarcoma-associated herpesvirus and human T-lymphotropic virus.

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14.

Viruses are the most abundant biological entity in aquatic environments.

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15.

Viruses are major agents responsible for the destruction of phytoplankton including harmful algal blooms, The number of viruses in the oceans decreases further offshore and deeper into the water, where there are fewer host organisms.

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16.

Viruses are an important natural means of transferring genes between different species, which increases genetic diversity and drives evolution.

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17.

Viruses are still one of the largest reservoirs of unexplored genetic diversity on Earth.

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18.

Viruses are important to the study of molecular and cell biology as they provide simple systems that can be used to manipulate and investigate the functions of cells.

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19.

Viruses have been modified by scientists to reproduce in cancer cells and destroy them but not infect healthy cells.

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20.

Viruses that have been reprogrammed to kill cancer cells are called oncolytic viruses.

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