Nature and distribution of viruses, Biology

Nature and Distribution of Viruses

Although several infectious diseases of animals and plants had been found to be caused by viruses during early 20th century, the true nature of these ultra micros copic pathogens could not be investigated. All attempts to cultivate these in chemical culture media failed, and it was found that these can be cultivated only in cultures of live cells and tissues, ultimately, in1935 W.M. Stanley  achieved success in isolating and crystallizing tobacco  mosaic virus  (TMV)and shared the1946 Nobel Prize for  this work with Northrop and Summer who had earlier crystallized an enzyme for the first time. The crystals prepared by him were found to be viable infect ants, i.e. these were capable of infecting tobacco leaves as usual. Hence it was established that viruses are not organisms, but only nonliving inanimate or inert ultramicroscopic particles capable of infecting live cell l sand causing serious in factious diseases. These particles are now called various.

Invention of electron microscopy by knoll and Ruska (1934) just a year before Stanley work triggered a fast growth in our knowledge about viruses during the last 5-6decades under a separate branch of study, called virology.

Being inanimate and ultramicroscopic particles, viruses are innumerable and occur everywhere in soil, water and air upon earth.

Posted Date: 9/26/2012 4:40:26 AM | Location : United States







Related Discussions:- Nature and distribution of viruses, Assignment Help, Ask Question on Nature and distribution of viruses, Get Answer, Expert's Help, Nature and distribution of viruses Discussions

Write discussion on Nature and distribution of viruses
Your posts are moderated
Related Questions
Describe the importance of Neuropsychological tests Neuropsychological tests are generally thought of as assessment instrument for a variety of cognitive, perceptual, and motor

A knotted network of capillaries within a nephron, the glomerulus, receives arterial blood and is porous enough to allow much of the fluid portion of the blood to flow out of it al

Water Absorption and Transpiration The rate of water absorption is controlled by the rate of transpiration. A high water potential in the atmosphere would reduce water loss fr

Q. Explain about ABCC11 GENE? Wax in the external canal of the human ear may be wet or dry. Whether earwax is wet or dry has been traced to a gene called ABCC11, found on ch

Cytoplasmic Matrix ( = cytosol  or Hyaloplasm ) This is the actual protoplasmic  part of the cytoplasm, containing dissolved proteins, electrolytes, glucose, etc. And forming

How would you design, in principle, an experiment to test the hypothesis that a certain variety of lettuce seed needed daylight in order to germinate?  You would need as large

Increase in cardio-thoracic ratio is a relatively specific indicator of left ventricular end-diastolic volume. Left atrial enlargement is seen as double density shadow, lifting up

Enumerate about the Reitan Aphasia Screening Test This test serves two purposes in that it contains both copying and language-related tasks. As an Aphasia screening procedure,


Many patients who are weak, fearful or shot of breath find it essential to hold tightly to the handrail while walking. If accurate aerobic information is to be obtained handrail su