which statement describes many of the structures involved in the first line of defense of the immune system hey they have contact with the external environment be there in ternal in contact with a pathogen through blood see they produce B cells in response to a pathogen D they produce T cells in the response to pathogen
Answers
Answer:
The adaptive immune system reacts specifically to pathogens (germs). It is able to recognize attacking pathogens and fights against certain antigens or foreign substances. The next time a known antigen is encountered, the adaptive immune system can respond faster.
When the immune system is weakened by the virus HIV, it is mostly a specific group of T cells that is reduced in number, the so-called T helper cells. Then the body is especially susceptible to infections by what are usually harmless pathogens. Due to the lack of T cells, the immune system has difficulties properly coordinating the fight against the pathogens in the tissue. People who have the immune deficiency AIDS often develop a bacterial inflammation of the lungs with streptococci or get fungal or herpes virus infections, for example.
Answer:
The correct answer would be They have contact with the external environment.
or: A
Explanation:
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