The ability to change immediately to a different surroundings has allowed plants to save giant volumes of energy as they germinate. Under the canopy the far-red light is predominant & the plants detect this information & the germination method changes. Skotomorphogenesis takes over & this causes different genes to be expressed & lets them escape the poor canopy light & discover areas of better light & hence greater productivity.
Being sessile plants must cope with a variable surroundings in a plastic way, adapting to the current surroundings whilst simultaneously being able to change if the stochastic process changes. Plants have evolved intricate mechanisms for interacting with the environment & this has guaranteed their success in climates that significantly differ from parents.
However, the plastic development does not occur above ground. The variability of ion concentrations within the soil must be exploited, & one time again, plants have an array of mechanisms for doing this. Usually the roots grow deep or laterally & spread themselves thinly to occupy all regions of the soil (& to an extent, help maintain support). When giant concentrations of nitrates are actively transported in to the root this causes a cascade of signalling molecules & the apical dominance is relieved. By doing this, energy can be diverted to axillary bud differentiation & thus the plant can have a high surface area of roots around the high concentration of Nitrates to maximize productivity.
Secondly, being sessile, plenty of plants such as Arabidopsis thaliana must be able to change to changes. The meristems monitor the populations of stem cells & dynamically regulate the production of new cells so balance the loss incurred from damage. Hormones, such as giberrelin travel from the damaged site to the axillary meristem at the bottom of the phytomer. The meristem would then extend as the stem cells inside began to divide & quickly increases it photosynthetic rate by producing more shoots.
Finally, a essential adaptation has allowed plants to form a symbiosis with bacteria & fungi in their roots to enable greater efficiency of nutrient intake when nutrients are low. By releasing flavonoids & through a complicated receptor derived pathways the plant provides metabolites for a species of Nitrosamona bacteria & also leghaemoglobin, mopping up Oxygen to prevent catalyst poisoning. The bacteria are then able to provide Nitrates to the plant.
In conclusion, the plants have evolved plenty of receptor pathways in order to sense the environment & grow accordingly. This has allowed the plants to have very an boundless variation of pherotypes in plenty of different environments, although genotype is present. This has allowed plants, specifically the angiosperms to become so successful even against very harsh environments & potentially this plasticity has allowed a more fast evolution.
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