Question

Which one of the following living tissues of plants generally lacks nucleus?

• A. Vessels of xylem
• B. Parenchyma of pith
• C. Cambium of roots
• D. Sieve tubes of phloem

Answer 1

Answer: (D)

Sieve tubes of phloem

1. Vessels of xylem are the long cylindrical tube-like structure made of many cells called as vessel members. These are connected by perforations and are the characteristic of angiosperms.
2. Pith or medulla are made of parenchyma and are present in stems of plants and helps in storage and transport nutrients throughout the plant.
3. Cambium is the actively dividing layers present in between xylem and phloem and responsible for secondary growth in dicots.
4. Sieve tube cells are long, elongated structure that is longitudinally arranged and are associated with the companion cells as they lack a nucleus.

So the correct option is "Sieve tubes of phloem".