Ectophloic siphonostele is found in -

Options

A. Osmunda and Equistum
B. Marsilea and Botrychium
C. Adiantrum and Cucurbitaceae
D. Deicksonia and Maiddenlair ferm.

Answer

A

Explanation

The stele is a column containing vascular tissues 1 which is surrounded by pericycle and separated from ground tissue by endodermis. Siphonostele is medullated protostele or protostele with a central non-vascular pith. Leaf gaps are absent. Siphonostele is of two types: In Ectophloic siphonostele, central pith is surrounded successively by xylem, phloem, pericycle and endodermis. In amphiphloic siphonostele there is a central pith and xylem is surrounded on either side by phloem, pericycle and endodermis, It is found in Osmunda and Equisetum.