Question

Tracheae or xylem vessels are long tube-like structures that are formed by cells stacked like coins. How is the presence of inner lumen explained here?

• A. The cells are ring shaped and therefore they can form a lumen when stacked.
• B. The cells are sclerenchymatous and have a lumen, plus they lack lateral cell walls
• C. The lumens of the cells are aligned to form a tube like structure
• D. Both b and c

Answer 1

The correct option is B

The cells are sclerenchymatous and have a lumen, plus they lack lateral cell walls

The cells of the xylem vessels stack one on top of the other with their lateral cell walls removed. Thus the lumen of these cells form a tube-like structure.