Plant perception (physiology) auxin redistribution occurs in a way to produce differential growth away from gravity. For perception to happen, the plant must sense, perceive and translate the direction of gravity. Without gravity, proper orientation will not occur and the plant will not effectively grow. The root will not be able to uptake nutrients or water, and the shoot will not grow towards the sky to maximize photosynthesis. Plants do not have a brain or neuronal network, but reactions within signalling pathways may provide a biochemical basis for learning and memory in addition to computation and problem solving. Controversially, the brain is used
Plant to plant communication via mycorrhizal networks have also initiated nutrient transfer by causing the movement of carbon from the roots of the stressed plant to the roots of a conspecific plant over a mycorrhizal network. Thus, nutrients transferred through mychorrhizal networks act as signals and cues to change the behavior of the connected plants. It is hypothesized that fitness is improved by the transfer of infochemicals through common mycorrhizal networks, as these signals and cues can induce responses which can help the receiver survive in its environment. Plants and fungus have evolved heritable genetic traits which influence their interactions with each other, and experiments, such as