Why is Sclerenchyma a dead tissue?

Sclerenchyma is considered a dead tissue primarily due to the presence of heavily lignified cell walls in its mature state. Lignin is a complex polymer that provides rigidity and strength to the cell walls, but it also renders the cells non-living and unable to perform typical cellular functions like metabolism or growth. Once sclerenchyma cells have completed their development and lignification process, they lose their cytoplasm and other organelles, becoming essentially empty shells supported by lignin. This structural specialization allows sclerenchyma to provide mechanical support and protection in plant tissues, such as in stems, roots, and seed coats.