Final answer:
In homeostasis, sweating to cool down body temperature and shivering to increase it are two examples of how the body maintains a stable internal environment, regulated by negative feedback loops under the control of the hypothalamus.
Step-by-step explanation:
The concept of homeostasis entails maintaining the internal environment of the body within a certain physiological range despite changes in the external environment. Examples of a properly functioning homeostatic response include sweating to cool down body temperature, shivering to warm up the body temperature, and other responses that aim to keep internal variables such as temperature and blood glucose level within the normal range.
Sweating is an effective homeostatic response to high internal temperatures. The hypothalamus, acting as the control center, detects the rise in body temperature and signals the sweat glands to increase their output, leading to evaporative cooling of the body. Conversely, shivering is a response to cold, where the hypothalamus triggers the muscles to rapidly contract and relax to generate heat and raise body temperature.
The increased heart rate during exercise and decreased breathing rate during sleep, while related to the body's adjustments to different situations, are not, strictly speaking, examples of homeostasis as they do not directly represent the maintenance of a stable internal environment against a variable external one.