Plant Kingdom – Pteridophytes: NEET MCQs with Answers

Explanation: Adiantum is a fern belonging to Pteropsida, not Sphenopsida; Sphenopsida includes Equisetum. Dryopteris (Pteropsida), Psilotum (Psilopsida) and Selaginella (Lycopsida) are correctly matched.

Explanation: In Equisetum (and Selaginella) the sporophylls are aggregated into compact terminal structures called strobili or cones. Pteris and Salvinia bear their sporangia in sori/sporocarps and Marchantia is a liverwort.

Explanation: In heterosporous pteridophytes such as Selaginella and Salvinia, the megaspore is retained on the parent sporophyte, the female gametophyte develops within it and the zygote grows into a young embryo there. This is the first appearance of the seed habit in plant evolution.

Explanation: The antherozoids of both bryophytes and pteridophytes are flagellated and must swim through a film of water to reach the mouth of the archegonium. This dependence on external water is why both groups are restricted to moist habitats.

Explanation: Pteridophytes are the most primitive vascular, flowerless, spore-producing cryptogamic land plants, and they are the first land plants to have an independent sporophyte with true roots, stem and leaves supported by a well-developed vascular system. Bryophytes lack vascular tissue and true roots, though both groups possess archegonia, flagellate sperms and an independent gametophyte.

Explanation: A well-developed archegonium with a long neck made of 4–6 rows of neck canal cells is characteristic of bryophytes and pteridophytes. In gymnosperms the archegonial neck is much reduced, and in angiosperms archegonia are absent altogether.

Explanation: Heterospory and the seed habit are often associated with the presence of a ligule — a small membranous outgrowth found at the base of the leaf in Selaginella and Isoetes, both of which are ligulate and heterosporous.

Explanation: The walking fern is so named because adventitious buds develop at its leaf tips; when the tips touch the soil they form new plants. This helps the fern spread over a large area of the soil surface, giving the impression that it is walking.

Explanation: Pteridophytes possess well-developed vascular tissue but do not bear seeds. Gymnosperms also have vascular tissue but they do produce seeds, while algae and bryophytes possess no vascular tissue at all.

Explanation: In ferns the sporangium is a diploid structure bearing diploid spore mother cells, which undergo meiosis to produce haploid spores. Each spore has an outer thick brown wall (exine) and a thin inner wall (intine), and is the first cell of the gametophytic generation.

Explanation: Eichler divided the plant kingdom into Cryptogamae and Phanerogamae. All plants without flowers and seeds are placed in Cryptogamae, which is further classified into Thallophyta, Bryophyta and Pteridophyta — hence spore-bearing mosses and ferns are collectively called cryptogams.

Explanation: A fern is a pteridophyte and Funaria is a bryophyte; both reproduce by spores and neither produces seeds. Ficus and Punica are angiosperms and Pinus is a gymnosperm, all of which are seed producers (phanerogams).

Explanation: The walking fern (Adiantum caudatum) propagates through its leaf tips: when the tips of the leaves come in contact with the soil they give out adventitious roots, which in turn produce new leaves and develop into new plants — so the fern appears to 'walk' across the soil surface.

Explanation: In an ectophloic siphonostele the central pith is surrounded successively by xylem, phloem, pericycle and endodermis — that is, phloem occurs only on the outer side of the xylem. This type is found in Osmunda and Equisetum. In the amphiphloic siphonostele, by contrast, xylem is flanked by phloem on both sides.

Explanation: When the male and female sex organs of the same prothallus mature at different times, the gametes are never available simultaneously on the same individual, so self-fertilisation is prevented and cross-fertilisation is promoted. Maturation of antherozoids before the egg is called protandry, and the reverse condition protogyny.