Which tissues constitute the plant's support tissues?

Which tissues constitute the plant's support tissues?

• A. Parenchyma and xylem
• B. Cortex and pith
• C. Xylem and phloem
• D. Collenchyma and sclerenchyma

Answer: (D)

The ability of a plant to stand upright and resist bending comes from tissues with thickened, tough cell walls. Collenchyma provides flexible support in growing parts like young stems and leaves; its cells are alive at maturity and have unevenly thickened primary walls that can stretch as the organ grows. Sclerenchyma offers rigid, strong support with thick, lignified secondary walls and is usually dead at maturity. It appears as fibers or sclereids and reinforces mature regions, making them rigid. Other options don’t serve as the main support tissues. Parenchyma is the general storage and metabolic tissue, not specialized for support. Cortex and pith are ground tissues that can contribute to overall structure but aren’t the primary supportive system. Xylem and phloem are the vascular tissues responsible for transport, not skeletal support. So, the plant’s support tissues are the collenchyma and sclerenchyma.

The ability of a plant to stand upright and resist bending comes from tissues with thickened, tough cell walls. Collenchyma provides flexible support in growing parts like young stems and leaves; its cells are alive at maturity and have unevenly thickened primary walls that can stretch as the organ grows. Sclerenchyma offers rigid, strong support with thick, lignified secondary walls and is usually dead at maturity. It appears as fibers or sclereids and reinforces mature regions, making them rigid.

Other options don’t serve as the main support tissues. Parenchyma is the general storage and metabolic tissue, not specialized for support. Cortex and pith are ground tissues that can contribute to overall structure but aren’t the primary supportive system. Xylem and phloem are the vascular tissues responsible for transport, not skeletal support.

So, the plant’s support tissues are the collenchyma and sclerenchyma.