Vascular bundles in monocotyledons are considered closed because:
Closed vascular bundles lack:
1. Ground tissue
2. Conjuctive tissue
3. Cambium
4. Pith
Some vascular bundles are described as open because these:
1. | are not surrounded by pericycle |
2. | are surrounded by pericycle but no endodermis |
3. | are capable of producing secondary xylem and phloem |
4. | possess conjunctive tissue between xylem and phloem |