Economics for Today 9th Edition by Irvin Tucker

Exercise 4

In this problem, we are asked to look at the natural supply and
demand curves for the organ market in the United States. The
important thing to note here is that the supply and the demand of
organs are both unrelated to changes in price. The only demand for
organs is from those that require a new one; people do not simply
want organs for other reasons. Similarly, those that are willing to
donate organs do not do so for any price, but out of the goodness
of his/her heart.