Considering the structural adaptations of sclerenchyma, which of these statements best explains why these cells are typically dead at maturity?
The heavily lignified cell wall restricts the entry of essential substances for cellular metabolism.
Sclerenchyma cells actively undergo programmed cell death during development to enhance structural integrity.
The lack of a nucleus and other organelles reduces the metabolic burden, optimizing the cell for support.
Sclerenchyma cells are produced in excess and are shed as the plant grows, similar to epidermal cells.
Related Questions
Which of the following statements is true?
The collenchyma occurs in layers below the epidermis in monocotyledonous plants
Sclerenchyma cells are usually dead and without protoplasts
Xylem parenchyma cells are living and thin-walled and their cell walls are made up of lignin
The companion cells are specialised sclerenchymatous cells
Which of the following is a characteristic feature of sclerenchyma cells?
Thin, permeable primary walls
Thick, lignified secondary walls
Presence of large intercellular spaces
Abundant cytoplasm
Sclereids are a type of sclerenchyma cell. Which of these is NOT a typical characteristic of sclereids?
Forming continuous, elongated fibers in plant stems
Occurring singly or in small groups within other tissues
Having highly thickened and lignified cell walls
Varying greatly in shape, from isodiametric to branched
Sclerenchyma provides mechanical support to plants. Which component of the cell wall contributes most to this strength?
Cellulose
Pectin
Lignin
Suberin
On the basis of variation in form, structure, origin and development, sclerenchyma may be
Fibres
Sclereids
Either (1) or (2)
Both (1) and (2)
Which specific characteristic of sclerenchyma cells primarily contributes to their exceptional strength and rigidity, making them suitable for providing structural support in plants?
Presence of lignin in the secondary cell wall
High concentration of pectin in the middle lamella
Presence of living protoplasts at maturity
Thin and flexible primary cell wall
What is the primary function of the pit canals found in sclerenchyma cells?
Transport water and minerals
Store food reserves
Facilitate communication between adjacent cells
Increase cell wall flexibility
Sclerenchyma mainly provides
Storage tissue to the plants
Mechanical support to the organs of plants
Secretory tissue to the plants
Strength to monocot plants, specially their abundance in the layers below the epidermis
Sclereids are a type of sclerenchyma cell. Which of the following best describes their shape?
Elongated and tapered
Varied shapes, often short and branched
Star-shaped
Cuboidal
Which statement correctly describes the relationship between the pit canals and the function of sclerenchyma fibers?
Pit canals allow for limited intercellular communication and nutrient transport, even though the cells are typically dead at maturity.
Pit canals are sites of active lignin synthesis, contributing to the thickening of the secondary cell wall.
Pit canals weaken the cell wall, providing flexibility to the sclerenchyma fibers.
Pit canals store water, allowing sclerenchyma cells to survive in arid conditions.
