Lacunate collenchyma is found in

Companion cells are closely associated with

How do mature sieve tubes differ from xylem vessels?

Lacunar collenchyma is found only in the hypodermis of:

The annular and spirally thickened conducting elements generally develop in the protoxylem when the root or stem is

While eating peach or pear,it is usually seen that some stone-like structures get entangled in the teeth. What are these stone-like structures called?