What term describes a physiological change cycle lasting about 24 hours?

The term that describes a physiological change cycle lasting about 24 hours is circadian rhythms. These rhythms are natural, internal processes that follow a roughly 24-hour cycle and are influenced by external factors such as light and temperature. Circadian rhythms play a crucial role in regulating various biological functions, including sleep-wake cycles, hormone release, and other bodily functions.

In contrast, homeostasis refers to the stable internal conditions maintained by the body, while chronobiology is the study of biological rhythms, including circadian rhythms. Metabolism encompasses the chemical processes that occur within organisms to maintain life but does not specifically refer to the cycle's timing. Thus, circadian rhythms are the most accurate term for a physiological process that repeats approximately every 24 hours.