Question

Polyarch condition is found in
A)Monocot root
B)Dicot root
C)Monocot stem
D)Dicot stem

Answer 1

Hint: It essentially means that 2 bundles of xylem are present inside the monocot root of the plant in botany when there is a polyarch state.

Complete answer:
Monocots have vascular bundles in a radial arrangement. Eight packets of xylem and phloem are contained in each of them. The condition, thus is denoted as polyarch. Xylem in the monocot root is known as exarch.
Xylem and phloem arise in distinct patches on alternate radii. Both root styles are distinguished by radial vascular bundles. The patch of xylem in the dicot root is 2 to 6 (diarch to hexarch). The xylem patch in the monocot root is 7 or more (polyarch)

1.Diarch status indicates that there are two xylem bundles, while hexarch status implies six xylem bundles.
2.The vascular bundles of the dicot root are classified as tetrarch and radial. There are four packets of alternately occurring xylem and phloem each. Xylem is known as the Exarch. There are eight Dicot stem vascular bundles, arranged in the shape of a split ring. The vascular bundles are found to be conjoint and collateral.
3.The arrangement in which the protoxylem is drawn to the periphery and metaxylem to the middle is Exarch. Endarch is the type of arrangement in which the protoxylem is oriented towards the middle and the periphery towards the metaxylem.

Hence, the correct answer is option (A)

Note: The conjoint vascular bundles are of two sorts, based on the volume and location of the phloem group: collateral type and bi-collateral type. Collateral vascular bundles are very common and are seen in dicotyledon stems, with the exception of Cucurbitaceae members and a few Convolvulaceae members.