Both from phyllogenetic and ontogenetic point of view, which tissue is regarded as most primitive

Distinguish between the following : Protoxylem and metaxylem

Conductive function is performed by

The chief water conducting elements of xylem in gymnosperms are

Find set of cells connected by pit fields between their common longitudinal walls

They provide mechanical support to the growing parts of the plant such as young stem and petiole of leaf.