Distinguish between Sieve cell and sieve tube member.

Sieve cell	Sieve tube member
1. Companion cells are absent.	These are usually associated with companion cells.
2. The end wall is broad.	The end wall is broad.
3. These are found in pteridophytes and gymnosperms.	These are found in angiosperms.
4. The pores are smaller but more numerous.	The pores are comparatively larger and fewer.