Anatomy and Physiology II Practice Test

What immunity develops after a person has had a disease?

1. Active natural immunity

2. Passive natural immunity

3. Active artificial immunity

4. Passive artificial immunity

The correct answer is: Active natural immunity

Active natural immunity develops when a person has been exposed to a disease-causing pathogen and their immune system responds by producing antibodies and memory cells specific to that pathogen. This type of immunity occurs naturally as a result of the body's own immune response to an infection. Once the individual has recovered, their immune system retains a memory of the pathogen, which can lead to a quicker and more effective response if the individual is exposed to the same pathogen again in the future. In contrast, passive natural immunity involves the transfer of antibodies from one individual to another, such as a mother to her baby through breast milk or the placenta. Active artificial immunity, on the other hand, results from deliberate exposure to a pathogen via vaccination, prompting the immune system to develop its own antibodies. Lastly, passive artificial immunity involves the introduction of pre-formed antibodies into an individual, often through medical treatments such as antibody therapy, which provides immediate but short-term protection. Each of these other forms of immunity serves different purposes and mechanics, while active natural immunity specifically refers to the immunity acquired through natural infection and subsequent recovery.