Question

page(s) 502-504 25.6. distinguish between a primary and a secondary adaptive immune response. complete the following passage regarding how the human body defends itself against pathogens. in the third line of defense, the human body initiates the immune response. this involves specific recognition of a particular pathogen with y - shaped proteins called that recognize invaders. upon first exposure, the immune response is activated. after several weeks or months, the body will produce memory cells that may recognize the pathogen in the future. these include mature lymphocytes such as. upon reexposure to this pathogen, the body can initiate a immune response, which will be faster than the previous response time. primary b cells nonspecific innate antibodies adaptive secondary phagocytes

Explanation:

The third line of defense is the adaptive immune response, which uses Y-shaped antibodies for specific pathogen recognition. First exposure triggers the primary response, producing memory cells like B cells. Reexposure initiates the faster secondary response.

Answer:

In the third line of defense, the human body initiates the adaptive immune response. This involves specific recognition of a particular pathogen with Y-shaped proteins called antibodies that recognize invaders. Upon first exposure, the primary immune response is activated. After several weeks or months, the body will produce memory cells that may recognize the pathogen in the future. These include mature lymphocytes such as B cells. Upon reexposure to this pathogen, the body can initiate a secondary immune response, which will be faster than the previous response time.