Question

which are the sieve tube elements found in angiosperm and gymnosperm

Answer 1

The sieve tube elements are the part of phloem tissue. These sieve tube elements are made up of the elongated cells, connected by the sieve plates. These sieve plates have the pores in it. The sieve tube elements loose, most of the organell to reduce the resistance in transport of the food. And most of the metabolic activities are done by the companion cells for them.