Question

Choose the correct option with respect to dicot stem:
i) Vascular bundles are arranged in a ring
ii) Exarch arrangement of secondary xylem
iii) Vascular bundles are conjoint, collateral and open type

• A. Only I is correct
• B. Only II is correct
• C. Both I and III are correct
• D. All (I, II and III ) are correct

Answer 1

The correct option is C Both I and III are correct

In dicot stems, the vascular bundles are arranged in a ring-like fashion around the pith. The dicot stem shows endarch condition of vascular bundles which means that the protoxylem is towards the inner side and the metaxylem is formed towards the periphery.
Exarch condition is usually seen in the roots of plants. The vascular bundles are conjoint (contain both xylem and phloem arranged in the same radius), collateral (xylem lies towards the inside and phloem towards the outside) and open ( shows the presence of cambium in between xylem and phloem).