The flu vaccine activates adaptive immunity. how does this occur? a vaccine introduces a weakened flu virus into the body. the immune system identifies antigens on the weakened flu virus. antibodies are quickly produced and allow the body to fight off the infection. the actual flu virus enters the body, and lymphocytes recognize the antigens. antibodies are produced, which bind to the weakened flu virus and signal immune cells to destroy it. put in order

Correct

A vaccine is a substance that stimulates the antibodies production and helps to provide immunity against one or more than one disease. It is made by taking a small amount of dead or whole weaned germs such as bacteria or virus that cause the disease.

When these weakened pathogens are introduced in the body they evoke the immune response inside the body and activates T- cells and B-cells inside the body, which prepare antibodies against that antigen in advance in order to save the body from infection by the same pathogen in the near future.

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

                                                   ↓

The actual flu virus enters the body, and lymphocytes recognize the antigens

                                                   ↓

Antibodies are quickly produced and allow the body to fight off the infection

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