Question

Which of the following characters are not applicable to the anatomy of the dicot stem?
I. Collenchymatous hypodermis
II. Polyarch xylem
III. The presence of casparian strips on the endodermis
IV. Open vascular bundle
V. The presence of medullary rays
Select the correct answer using the codes given below:

• A. I, IV and V
• B. II and III
• C. II and V
• D. I, II and III
• E. III, IV and V

Answer 1

The correct option is B

II and III

The hypodermis in the dicot stem is made of collenchyma and may be green, that is, it may contain chlorophyll. The presence of polyarch xylem and casparian strip are features of the root. So, it is not found in the stem. The dicot stem does have an open vascular bundle and is hence capable of secondary growth. The dicot stem also has medullary rays, which are strips of parenchyma between vascular bundles. Hence, only the statements II and III are inapplicable to the anatomy of the dicot stem.