Question

Companion cells are usually seen associated with

• A. Fibres
• B. Parenchyma
• C. Xylem vessels
• D. Sieve tubes

Answer 1

Answer: (D)

Sieve tubes

Sieve cells are tube like elongated cells in the phloem. These are the main conducting elements in the phloem tissue. The sieve tubes are the cells with no nuclei or the nuclei is fragmented. The companion cells present adjacent to the sieve tube cells have a nucleus. The nucleus of the companion cells performs the functions for both the cells. Hence, the companion cells are called as life support cells for the sieve tubes.