It is a common misconception that most of the solid material in a plant is taken from the soil, when in fact almost all of it is actually taken from the air. Through a process known as photosynthesis, plants use the energy in sunlight to convert carbon dioxide from the air into simple sugars. These sugars are then used as building blocks and form the main structural component of the plant. Plants rely on soil primarily for water (in quantitative terms), but also obtain nitrogen, phosphorus and other crucial nutrients.
The growth rate of plants is extremely variable. Some mosses grow less than 0.001 mm/h, while most trees grow 0.025-0.250 mm/h. Some climbing species, such as kudzu, which do not need to produce thick supportive tissue, may grow up to 12.5 mm/h.
Some plants grow special defence measures such as the spines on a blackberry
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