Which part of the root contains transport tubes?

The part of the root that contains transport tubes is the root hair. The primary role of the root hair is to absorb water and nutrients from the soil. They are hair-like and tubular in structure and are sometimes rarely visible by the naked eye. 

The root contains hair-like tiny roots that suck nutrients from the soil.Other trees there roots are hanging on their branches such Banyan trees.
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Allow large amino acids through

True but only in the south coastal areas during september and early october.