Final answer:
A plant is most likely in the germination stage when it relies on stored compounds due to temperature changes. During germination, a seed uses stored energy to grow until it can reach enough light for photosynthesis. The correct option is 2) germination.
Step-by-step explanation:
When plants must rely on compounds stored in their organs due to temperature changes, this typically occurs during the germination phase. During germination, a seed will utilize stored nutrients to grow until it can reach sufficient light for photosynthesis. Environmental cues such as the change of seasons and photoperiods influence phenological events, like germination, seasonal leaf shedding, and flowering in plants.
Seasonal changes can prompt plants to enter into a dormant state, particularly in colder temperatures when photosynthesis is less efficient or not possible. In such cases, the energy stored in the seed is critical for the seedling's survival. Nurseries may factor in the photoperiodic response of plants to plan the lighting schedules required for the growth and flowering of plants, understanding that certain light periods and colors are most effective for these processes.
Therefore, the stage in which a plant is most likely to rely on stored compounds due to temperature changes is germination. This is essential for a seedling that might be growing in shade and does not have access to sufficient light to promote photosynthesis immediately. The stored reserves give the seedling a chance to continue to grow until it can reach better light conditions.
In summary, the correct option when a plant relies on stored compounds because of temperature changes, especially during cold seasons or in shaded conditions is option 2) germination.