Question

Why are sieve tubes in gymnosperms and pteridophytes called sieve cells?

Answer 1

Sieve cells:

1. Sieve cells are the main conducting part of the phloem.
2. These are seen in gymnosperms and pteridophytes.
3. Sieve cells are primitive with narrow pores and no sieve plates.
4. There are no linear rows of sieve tubes thus, they are called sieve cells.
5. Sieve cells have a tapering end wall and are elongated cells.
6. Sieve cells help in the transportation of food to various parts of the plant.