Recapitulation is a bold and influential idea that is particularly associated with Ernst Haeckel though many other biologists also supported it in the nineteenth and early twentieth centuries. According to the theory of recapitulation, the stages of an organism’s development correspond to the species’ phylogenetic history- in a phrase, “ontogeny recapitulates phylogeny.” Each stage in development corresponds to (that is, [...]
Here is an essay on ‘Bacteria and Human Disease’ for class 11 and 12. Find paragraphs, long and short essays on ‘Bacteria and Human Disease’ especially written for school and college students. Essay on Bacteria and Human Disease Essay # 1. Brucella Abortus: Cells short ellipsoidal rods, occurring singly, in pairs, and occasionally in chains, measuring 0.3 to 0.4 μ [...]
Here is a list of seven effective physical agents that can kill infection causing organisms:- 1. Electricity 2. Sonic and Supersonic Waves 3. Alpha, Beta, and Gamma Rays 4. Electrons 5. Cathode Rays 6. X Rays 7. Distilled Water. Physical Agent # 1. Electricity: Beattie and Lewis (1920) employed a current of about 4000 volts and 2 amp. for 4 [...]