The term, 'vaccination' originated from vacca which means cow. The term was first used by Edward Jenner who discovered (1798) that cow-pox induced immunity to small-pox in persons artificially inoculated with cow-pox. This process of inducing immunity against small pox came to be known as vaccination which saved millions of human lives since then and has eventually led to complete [...]
Here is an essay on the nitrogen cycle. Nitrogen is one of the important elements in biological compounds, mainly of nucleic acid and protein and, therefore, it is essential for life. Atmosphere contains about 78% nitrogen, but free nitrogen cannot be utilised by most of the organisms, except a few blue green algae and some bacteria. The fixation of nitrogen [...]
In this essay we will discuss about:- 1. History of Bird Flu 2. Symptoms of Bird Flu 3. Causative Agent 4. Prevention 5. Dissemination 6. Persons in Danger 7. Caution from WHO 8. Available Drugs. Essay on the History of Bird Flu: Bird flu or avian influenza is a viral disease of birds — it spreads in different countries by [...]