Which of these statements about a monocot stem is false ?

Options

A. The hypodermis in monocot stem is made up of sclerenchyma.
B. The layer of pericycle just below the endodermis is generally absent.
C. Central vascular bundles are generally smaller then the peripheral vascular bundles.
D. Each vascular bundle is conjoint , closed and with endarch protoxylem.

Answer

To determine which statement about a monocot stem is false, we will analyze each statement provided in the question.

1. **The hypodermis in monocot stem is made up of sclerenchyma.**
- This statement is **true**. In monocot stems, the hypodermis is typically composed of sclerenchyma, which provides support and protection.

2. **The layer of pericycle just below the endodermis is absent.**
- This statement is also **true**. In monocot stems, the pericycle layer is indeed absent, which differentiates them from dicot stems.

3. **Central vascular bundles are generally smaller than the peripheral vascular bundles.**
- This statement is **false**. In monocot stems, the vascular bundles are typically scattered throughout the stem and are often of similar size, rather than having a distinction between central and peripheral bundles. This characteristic is more associated with dicot stems, where the vascular bundles are arranged in a ring and can vary in size.

4. **Each vascular bundle is conjoined, closed, and indarch protoxylem.**
- This statement is **true**. In monocots, the vascular bundles are conjoined (xylem and phloem are adjacent), closed (no cambium present), and the protoxylem is positioned towards the center (indarch).

Based on the analysis, the false statement regarding monocot stems is:

**Answer: Central vascular bundles are generally smaller than the peripheral vascular bundles.**