Final answer:
An effector in a biology-focused negative feedback loop causes changes that reverse a deviation from a set point to maintain homeostasis, illustrated by the example of body temperature regulation where sweat glands reduce body temperature.
Step-by-step explanation:
The subject of this question is Biology, focusing on the concept of negative feedback loops in maintaining homeostasis. An effector in a negative feedback loop is responsible for causing change that reverses a deviation from the set point to return a physiological value to its normal range. For example, if the body temperature rises above the set point, the temperature regulatory centers in the brain (the control center) would activate sweat glands (effectors) to cool the body down. Once the body temperature returns to the normal range, it provides negative feedback to stop the sweat glands from producing more sweat.
Considering a negative feedback loop in the regulation of blood glucose levels, an example of an effector might be the pancreas releasing insulin. If blood glucose levels rise above the set point, the pancreas (effector) secretes insulin to help lower the glucose levels back to the normal range. Conversely, if the glucose levels fall below the set point, the pancreas may secrete glucagon to increase the glucose levels.