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Sindrei [870]
3 years ago
15

The concentration of pathogen needed to kill 50% of an infected group of test animals is the __________.

Biology
1 answer:
natulia [17]3 years ago
6 0

Answer:

LD50 (median lethal dose)

Explanation:

  • Whenever one needs to quantify the virulence of a pathogen then this is done by using a set of laboratory animals.
  • LD50 (median lethal dose) is an important indicator of virulence. 
  • LD50 is defined as the number of pathogens that are required to kill 50% of the total infected animals.
  • For the calculation of LD50, the animals are infected with a known number of pathogens and then a graph is plotted for the percentage of animals killed against the concentration of the pathogen used for infection.<em> The point at which the graph indicates the death of 50% animals, the corresponding concentration of inoculation of a pathogen is taken as the LD50 of that particular pathogen. </em>
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