Question

Sieve cells & Sieve tubes both are phloem elements. Yet they differ. How?

Answer 1

Sieve cells	Sieve tubes
Have no companion cells	Have companion cells
The sieve areas do not form sieve plates	The sieve areas are confined to sieve plates.
The sieve areas are not well differentiated	The sieve areas are well differentiated
They are elongated cells and are quite long with tapering end walls	They consist of vertical cells placed one above the other forming long tubes connected at the walls by sieve pores
The sieve are smaller and numerous	The sieve pores are longer and fewer
Found in Pteridophytes and Gymnosperms	Found in Angiosperms