Question

Which of the following is/are composed of dead cells?
A. Sclerenchyma
B. Tracheids
C. Vessels
D. All of the above

Answer 1

Hint: The cell which is composed of the dead is Sclerenchyma it is a permanent tissue which provides the strength, support, and transportation of water and also supplies nutrients to the plant

Complete answer: The sclerenchyma is mainly composed of the dead cells which provide the strength and rigidity to the stem. It also provides a protective covering to the nuts and fruits as the cell walls consist of a high proportion of lignin and cellulose.
These cells are located in the leaf veins, hard covering of the seeds, and also in the vascular bundle. Sclerenchyma is present in the form of fibers or sclereids i.e. the stone cells.

Additional information: Sclerenchyma cells get both thicker walls and die off at maturity, forming tissues like bark and vascular tissue.
In fact, most photosynthesis occurs within specialized parenchyma cells found within leaves. These parenchyma cells, called chlorenchyma cells, consist of chloroplasts.

Hence, the correct option is ‘A.’

Note: The structural materials in support of the tissues of vascular plants is the Lignin which is the complex organic polymer. Lignin is abundant in some of the cell walls where it has the function of mechanical support resistance to the stress and water transportation.