Vascular bundles in monocotyledons are considered closed because:
1. | a bundle sheath surrounds each bundle |
2. | cambium is absent |
3. | there are no vessels with perforations |
4. | xylem is surrounded all around by phloem |
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 |