Question

Periderm is formed from

• A. Vascular cambium
• B. Phellogen
• C. Fascicular cambium
• D. Interfascicular cambium

Answer 1

The correct option is B Phellogen

The periderm is the secondary protective tissue that replaces the epidermis during growth in thickness of stems and roots. The periderm is a multilayered tissue system, the bulk of which usually constitutes the cork or phellem. Phellem (the cork) consists of cells that are dead at maturity and their primary walls become covered from the inside by the secondary wall, which consists of parallel suberin lamellae alternating with wax layers. The lateral meristem or phellogen is one cell layer thick and encircles the stem. It produces periderm centrifugally.