Question

In the diagram of T.S. of stele of a dicot root, the different parts have been indicated by alphabets; choose the answer in which these alphabets correctly match with the parts they indicate.

• A. A-Endodermis, B-Conjunctive tissue, C-Metaxylem, D-Protoxylem, E-Phloem, F-Pith
• B. A-Endodermis, B-Pith, C-Protoxylem, D-Metaxylem, E-Protoxylem, F-Conjunctive tissue
• C. A-Pericycle, B-Conjunctive tissue, C-Metaxylem, D-Protoxylem, E-Phloem
• D. A-Endodermis, B-Conjunctive tissue, C-Protoxylem, D-Metaxylem, E-Phloem, F-Pith

Answer 1

The correct option is D A-Endodermis, B-Conjunctive tissue, C-Protoxylem, D-Metaxylem, E-Phloem, F-Pith

• The innermost cortical layer is called endodermis. Its cells are barrel-shaped and are closely packed. Many cells get suberized on their radial and inner walls. These thickenings are called casparian stripes.
• Between xylem and phloem elements, parenchyma cells are present constituting conjunctive tissue, which later becomes a secondary meristem.
• Xylem and phloem patches are in equal numbers and alternate with each other. Xylem or phloem patches are usually four in number. In the xylem, the protoxylem elements face pericycle. Pith is very small, with closely packed parenchyma cells.

Thus, the correct answer is option D.