Answer:
The correct order would be:
A vaccine introduces a weakened flu virus into the body.
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The immune system identifies antigens on the weakened flu virus.
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Antibodies are produced, which bind to the weakened flu virus and signal immune cells to destroy it.
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The actual flu virus enters the body, and lymphocytes recognize the antigens.
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Antibodies are quickly produced and allow the body to fight off the infection.
Vaccination or immunization is the process which helps in developing the immunity (adaptive) against a particular pathogen or microorganism.
It includes the administration of antigen, weakened or heat-killed microorganism (such as flu virus) into the patients body. Body's immune system produces naive B and T cells to eliminate the antigen.
This encounter enables the immune system to produce memory B and T cells against that particular pathogen.
In future, whenever the same antigen enters the body, the immune system gets activated quickly due to the presence of memory cells. It enables the body to produce more effective secondary response against the pathogen.
I think the correct answer would be the third option. Organisms that help break down dead organic material so it can be recycled into a usable form for other organisms are called decomposers and this would include some of the bacteria. Also, there is a number of bacteria that are capable of breaking down some of the harmful products like in recent studies there are bacteria that could dechlorinate the toxic PCB substance. Some bacteria, as well, lives in the human intestines which aids in the breaking down of the food into useful molecules. The third option is partially true since there are some bacteria like the cyanobacteria which produces oxygen but it does not contribute largely to the oxygen present in the atmosphere.
<span>The scientific study of the distribution and
abundance of organisms and the interactions that determine distribution
and abundance. This definition encompasses not only the plants and
animals that Haeckel recognized but microscopic organisms such as Bacteria, Archaea and protozoa, as well.</span>
Answer:
<em>expenditures for search engine advertising</em>
Explanation:
In the field of business, internet marketing has become a new and advances business practice. Search engine can be described as a method by which online advertisements are made The search advertising can be considered to be an alternative for the SEO and the SEM.
By paid advertisements, the advertisers can occur first in the search engine result page which might beneficial to their business.