Final answer:
True, set points like blood pressure can increase and the body may adjust to consider the higher level as the new normal, thereby not attempting to reduce it to the initial set point without intervention such as medication.
Step-by-step explanation:
The concept of a set point in biology refers to the stable state that a system's feedback loop aims to maintain. Regarding the statement that set points can go up but rarely go down, it is true, particularly in the context of physiological systems like blood pressure.
As an example, if an individual's blood pressure continues to increase over time, the body can adjust and recognize this new higher level as the normal set point.
Consequently, the body no longer perceives this elevation as abnormal and does not try to lower it back to the initial set point, maintaining an elevated blood pressure unless actively lowered through medication.
This modification of the set point is a clear illustration of the alteration process of a set point within a feedback loop.