The human body naturally tends to follow a cycle of sleeping and waking that corresponds to a:

The appropriate response is the circadian musicality of a 24-hour cycle. A circadian musicality is an approximately 24 hour cycle in the physiological procedures of living creatures, including plants, creatures, organisms and cyanobacteria. In a strict sense, circadian rhythms are endogenously produced, despite the fact that they can be balanced by outside prompts, for example, daylight and temperature.

That is true tge cactus as a structural adaptation to its envirinment has it leaves reduced to spines. but this doesnt mean it cant produce food it produces food because of the presence of chlorophyll in its stem

Sugar + oxygen > carbon  dioxide + water + energy  c6h1206 + 6o2 > 6co2 +6h2o + energy  and the numbers after the element symbols are small.