Final answer:
Diurnal organisms are active during the day and align with daylight patterns, contrasting with nocturnal animals that are active at night. Both behaviors are part of the circadian rhythms, which govern daily behavioral cycles.
Step-by-step explanation:
The term that describes an organism that is active during the day is diurnal. Animals that fall into the diurnal category typically wake up with the sunrise and go to sleep at sunset, following the patterns of daylight. In contrast, nocturnal animals are active at night and rest during the day. This behavior is part of an animal's circadian rhythms, which are approximately 24-hour cycles of behavior, including sleeping and waking, that are found in most eukaryotic organisms.