Question

Vascular bundles of monocot stem are:
A. Conjoint, collateral and open
B. Conjoint, collateral and closed
C. Conjoint, bicollateral and open
D. Conjoint, concentric and closed.

Answer 1

Hint: Monocot plants are those plants whose seeds have a single cotyledon. They usually lack secondary growth. The xylem, phloem and the cambium (if present) are together known as the vascular bundles. The vascular bundles are of various types depending on the arrangement of the xylem and the phloem.

Complete answer:
To know the correct answer, we must be aware of the different types of vascular bundles.
Conjoint vascular bundles are those in which the xylem and the phloem are arranged on the same radius.
Collateral vascular bundles are those in which the cambium is present on the outside of the xylem.
Open vascular bundles are those in which the cambium is present between the xylem and the phloem while the closed vascular bundles are those in which no cambium is present between the xylem and the phloem.
Bicollateral vascular bundles are those in which the phloem patches are present on either side of the xylem.
Concentric vascular bundles as the name suggests are those in which either the xylem is surrounded by the phloem or the phloem is surrounded by the xylem.

Since now we are well aware of the vascular bundles of the monocot stem, therefore, the correct answer to the question is conjoint, collateral and closed.

Note: Here it must be noted that in monocot stem the vascular bundles are scattered and arranged in oval shape. Bundle sheath is present around them. The vascular bundles in the periphery are smaller as compared to those in the centre.