Simple answer - NO. Xylem is actually dead tissue and, in all but the order Myrtales, is inside a layer of tissue called the phloem and outside the pith. (The order Myrtales also has an inner layer of phloem ie. one either side of the xylem.) Xylem eventually compresses to become wood. It is responsible for the upward transport of water and nutrients. Phloem is living tissue and is responsible for downward transport of photosynthates, plant hormones etc.

Definitely No. It is only found in plants system as a transporting agent, whereas other organism have their own unique transporting agents within their system.

No.

11 years old - junheng