Your Father Has Just Been Diagnosed with Rheumatoid Arthritis

question 86

Multiple Choice

Your father has just been diagnosed with rheumatoid arthritis. He has pain and the sensation of "pins and needles" in some if his finger joints and also in his wrists. He knows you covered autoimmune diseases in your microbiology class, so asks you to help him understand his condition.
-You explain to your father that usually, the immune system routinely eliminates or silences any lymphocytes that recognize autoantigens, which are the "self" antigens found in cells and on body tissues. This process is called self-tolerance. In autoimmune disease, self-tolerance is faulty. There are at least two mechanisms that lead to self-tolerance. Which are they?
1) Negative selection of developing lymphocytes that recognize autoantigens, resulting in apoptosis of those cells.
2) Introduction of antigen by the oral route, so that the immune system "learns" to tolerate it, just as it does the many antigens ingested in food.
3) Failure of naive lymphocytes that recognize antigen but do not receive the necessary second signals (MHC) to become responsive.

• A) 1 and 2
• B) 1 and 3
• C) 2 and 3
• D) 1, 2, and 3
• E) 1 only

---

Definitions:

ATC

Average Total Cost; the total cost of production (fixed and variable costs combined) divided by the number of units produced.

Price Charged

The amount of money a buyer has to pay to acquire a product or service from a seller.

Marginal Revenue

The revenue that a company gains by selling an additional unit of a product, indicating the income effect of increasing output by one unit.

Marginal Cost

The additional financial burden of creating another unit of a product or service.