Question

Radial vascular bundles occur in
A. Stem
B. Monocot root
C. Dicot root
D. Both monocot and dicot roots

Answer 1

Hint: The arrangement of conducting vessels in the stem or leaves of a plant.

Complete answer:
The radial vascular bundle is a simple arrangement of the xylem and phloem side by side on different radii and are separated by non-conductive tissues.
These radial vascular bundles are the characteristic feature of the root of both dicots and monocots.

Additional information:
- The radial vascular bundle is the presence of xylem and phloem in patches.
- Several vascular bundles vary from 2-6 in dicot root, whereas numerous vascular bundles are present in monocot roots.
- Vascular bundles are mainly of four types:
1. Collateral bundle – a vascular bundle where the strand of phloem is present external to the strand of xylem in the same radius. It is two types: closed collateral bundle and open collateral bundle.
2. Bicollateral bundle – a vascular bundle where phloem is situated on the periphery and inner side of xylem.
3. Concentric bundle – a vascular bundle in which one type of vascular bundle surrounds the other. It is of two types: amphivasal bundle and amphicribral bundle.
4. Radial vascular bundle – a vascular bundle in which primary xylem and phloem strands are separated by non-vascular tissues.
- They are part of the transport system in vascular plants.

So, the correct answer is Both monocot and dicot roots.

Note: The vascular bundle is arranged in a ring, with the pit concentrated at the core of the stem, rather than being scattered throughout the plant interior. In each vascular bundle, the xylem and phloem are separated by a substance called vascular cambium.