Kaplan Nursing Entrance Practice Exam

What occurs in autoimmune disorders?

1. The immune system strengthens its defenses against germs

2. The body begins tolerating foreign substances

3. The immune system attacks the body’s own tissues

4. The body enhances its barriers to foreign invaders

The correct answer is: The immune system attacks the body’s own tissues

In autoimmune disorders, the immune system mistakenly identifies the body’s own tissues as foreign invaders and launches an attack against them. This abnormal immune response can lead to inflammation and damage to various organs and systems within the body. Conditions such as rheumatoid arthritis, lupus, and multiple sclerosis exemplify this phenomenon, where the immune system's malfunction results in the targeting of healthy cells, tissues, and organs, causing a range of symptoms and health complications. The other options do not accurately describe the mechanisms involved in autoimmune disorders. Strengthening defenses against germs relates to a typical immune response to infections. Tolerating foreign substances is more associated with immunological tolerance, which is crucial in preventing the immune system from attacking non-harmful antigens, such as food and healthy gut bacteria. Enhancing barriers to foreign invaders generally refers to physical and physiological defenses, such as skin and mucous membranes, rather than the misdirected attacks seen in autoimmune conditions.