Final answer:
Transpiration is important for plants because it provides water for photosynthesis, helps cool the plant, and replaces water lost through evaporation.
Step-by-step explanation:
Transpiration is important for plants because it serves multiple functions. Firstly, transpiration helps in the uptake of water and nutrients from the roots to the leaves. It provides water for important biological processes in the plant, particularly for photosynthesis, which requires water as a reactant. Secondly, transpiration helps in cooling the plant. As water evaporates from the leaves, it cools down the plant, similar to how sweating cools down our bodies. Lastly, transpiration helps in the transport of minerals and sugars throughout the plant. As water is lost through transpiration, it creates a pulling force, called transpirational pull, which helps in the movement of water and nutrients up the plant. Therefore, all of the above options - water is needed for photosynthesis, it helps cool the plant, and it replaces water lost through evaporation - are correct.
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