Question

A condition found in roots of a plant having assimilatory submerged roots and spongy petioles
(a) Tetrarch
(b) Triarch
(c) Monarch
(d) Diarch

Answer 1

Hint: Based on the number of xylem strands present in the stele, it can be of different types. Among this, roots of a plant having assimilatory submerged roots and spongy petioles are found in a type with a single strand of xylem in the stele.

Complete step by step answer:
Monarch is a condition found in the roots of a plant having assimilatory submerged roots and spongy petioles. They have stele with 1 xylem strand. example: Trapa.
Tetrarch stele - the stele with 4 xylem strands. For example Gossypium.
Triarch stele - the stele with 3 xylem strands. An example of it is Pisum.
Diarch stele - stele with two xylem strands - eg: Nicotiana.

According to the older botanists, the vascular tissue is that the fundamental unit within the system of pteridophytes and better plants. Van Tieghem and Douliot (1886) interpreted the plant body of a vascular plant in a different way.
According to them, the elemental parts of a shoot are the cortex and a central cylinder is understood as stele. Thus the stele is defined as a central vascular cylinder, with or without the presence of pith and delimited the cortex by endodermis.
So, the correct answer is, ‘Monarch.’

Note: In a vascular plant, the stele is the central portion of the root or stem containing the tissues derived from the procambium. These include plant tissue, in some cases ground tissue (pith) , and a pericycle, which, if present, defines the outermost boundary of the stele. In other words, vascular tissue or the stele consists of three tissues: the pericycle, the xylem, and also the phloem.