Question

Which one of the following is a vascular cryptogram?
A. Equisetum
B. Ginkgo
C. Marchantia
D. Cedrus

Answer 1

Hint: Tracheophytes are also called vascular plants and are thought to represent a natural group, that is, they are closest relatives to each other and are all descendants of a common ancestor.

Complete Answer:
- The seed-free vascular plants are sometimes referred to as cryptogams.
- In other words, the reproductive components of these plants are relatively ambiguous-they are free of flowers and seeds. At maturity, all generations, gametophytes and sporophytes, are separate.
- The name was originally given to those classes of plants that have well-developed pinnate or frond-like leaves. Pteridophyta (Gr, Pteron = feather, phyton = plant), Pteridophytes are cryptogams that have well formed vascular tissue (Gr. kruptos = secret, and Gamos = wedded). Most of the living Pteridophytes are terrestrial and tend to grow in cool, moist and shady areas.
- Most of the Pteridophytes are herbaceous, but others are perennial and tree-like. The body of the plant is sporophytic and can be distinguished into root, stem and leaves. With monopodial or dichotomous branching, roots are adventitious in nature. Diarch is typically internally. Generally, the stem is branched. Branching is dichotomous or monopodial.
- Branches in the axil of the leaves do not occur. In several Pteridophytes, rhizomes represent the stem.
- Leaves can be small, thin, scaly (e.g. Equisetum, microphyllous), simple and sessile (e.g. Selaginella) or broad and pinnate (e.g. Dryopteris, Adiantum megaphyllous).
- The vascular tissue of the stem and root is present. It's made of phloem and xylem. Xylem consists only of tracheids, and phloem consists only of sieve tubes.
- Protostele (e.g Rhynia, Lycopodium), siphonostele (e.g Equisetum), Adiantum dictyostele) or polycyclic (e.g Angiopteris) are steel. Cambium is absent; hence they do not show secondary growth.

The correct answer is option(A) Equisetum.

Note: There are about 12,000 species of pteridophytes worldwide, so they are a big group. Cryptogams, as Linnaeus, who used the term, did not know how they replicated, means secret marriage. The pteridophytes refer to"the ferns and allies of the ferns.