Innermost layer of cortex isA) PericycleB) EndodermisC) CutinisedD) Suberised

The correct answer is: B) Endodermis
The cortex of a plant root or stem is located between the epidermis and the vascular tissue. It plays a crucial role in the storage of food and water. The innermost layer of the cortex in most plant roots and stems is the endodermis.
1. Endodermis (Option B):
• The endodermis is the innermost layer of the cortex in roots and stems, which surrounds the vascular bundle.
• This layer plays a critical role in controlling the flow of water and nutrients into the vascular system through the Casparian strip. The Casparian strip is made of suberin (a waxy substance), which prevents the passive flow of substances and forces them to pass through the cell membrane, allowing the plant to regulate which substances enter the vascular system.
2. Pericycle (Option A):
• The pericycle is the layer of cells found just inside the endodermis, surrounding the vascular tissue. It plays a role in the formation of lateral roots.
• It is not the innermost layer of the cortex but is located just outside the vascular bundle.
3. Cutinized (Option C):
• Cutin is a waxy substance found in the epidermis of plants, particularly on the outer surfaces of leaves and stems, forming the cuticle. This helps prevent water loss.
• Cutinization is not related to the innermost layer of the cortex.
4. Suberised (Option D):
• Suberin is a waxy substance found in the cell walls of certain tissues, including the endodermis. It is part of the Casparian strip in the endodermis, not a separate layer.
• Suberization refers to the process by which suberin is deposited in cell walls, particularly in the endodermis, but suberised does not refer to a distinct layer by itself.
The innermost layer of the cortex is the endodermis, and it plays a vital role in regulating the passage of water and minerals into the vascular system of the plant. Therefore, the correct answer is B) Endodermis.