Microbiology Practice Exam

Vaccines provide acquired immunity, which is also known as adaptive immunity. This type of immunity develops as a result of exposure to a specific antigen, which is often introduced via a vaccine. When a person receives a vaccine, they are exposed to a harmless form or component of a pathogen, such as a weakened or inactivated virus, or a piece of its protein. This exposure stimulates the immune system to develop a response, including the production of antibodies and memory cells that specifically target the pathogen.

Acquired immunity is characterized by two key features: specificity and memory. The immune system learns to recognize specific pathogens and can respond more rapidly and effectively upon subsequent exposures. This is different from innate immunity, which is the body's first line of defense and responds the same way to all pathogens without the need for prior exposure.

Passive immunity, on the other hand, involves the transfer of pre-formed antibodies from one individual to another, such as from mother to infant through breast milk or through antibody therapies. This immunity is temporary and does not involve the immune system's own response to the pathogen.

Natural immunity refers to immunity acquired through natural exposure to pathogens, resulting in either an illness followed by recovery or through normal life circumstances, which can develop an innate response.

Thus,