Question

Assertion (A): All the endodermal cells of the root do not contain casparian thickenings on their radial and transverse walls. Reason (R): Passage cells are found in the Root endodermis.

• A. Both (A) and (R) are true and (R) is the correct explanation of
• B. Both (A) and (R) are true but (R) is not the correct explanation of
• C. (A) is true but (R) is false
• D. (A) is false but (R) is true

Answer 1

Answer: (B)

The characteristic feature of endodermal cells of roots is the presence of casparian thickenings on their radial and transverse walls but all cells of endodermis do not have casparian thickenings instead they have simple permeable cell wall. These cells are called passage cells which remain in contact with the protoxylem cells. Passage cells provide rute for the movement of water from cortex to xylem. Here assertion and reason both are correct but reason is not a correct explanation of assertion.