Plant Biology and Classification

Pteridophytes have a well-developed vascular system and naked embryos called spores. The reproductive organs are very inconspicuous (not visible) and therefore, are called “cryptogamae” or “those with hidden reproductive organs”. Therefore, no formation of seed occurs. Thallophytes and bryophytes are also known as cryptogams, e.g. fern.  

The plants of this group bear naked seeds and are usually perennial (is a plant that lives for more than two years), evergreen and woody plants, e.g. Pinus, Deodar.

Reason: Amphibian - means land animal that breeds in water Bryophyte represents a unique group of plants intermediate between the predominantly aquatic thallophytes and terrestrial pteridophytes. They occupy and inhabit a zone, which is neither completely land nor completely water. It is for this reason bryophytes are often regarded as amphibians of plant kingdom. Like amphibians, bryophytes also can survive on land and require water for fertilization. 

Like other land plants, they have multicellular sex organs but do not bear seeds, e.g. mosses and marchantia.

Reason: Bryophyte represents a unique group of plants intermediate between the predominantly aquatic thallophytes and terrestrial pteridophytes. They inhabit a zone, which is neither completely land nor completely water. Thus, bryophytes are often regarded as amphibians of plant kingdom. Like amphibians, bryophytes can survive on land and require water for fertilization. Mostly, the plant body of bryophytes is differentiated to form stem and leaf like structures. However, there is no specialized tissue for the conduction of water and other substances from one part of the plant body to another. Examples are moss and marchantia. 

Marsilea - is an aquatic fern. As it is a fern, it belongs to pteridophyta.

Pteridophytes are known as vascular cryptograms.

Cryptogams are non-flowering plants.

Except Riccia, all are thallophytes.

Bryophytes are called 'amphibians' of the plant kingdom.

Bryophytes are called the amphibians of the plant kingdom because they require water for fertilization, similar to how amphibians require water for their life cycle.

Sporogonium in Marchantia is parasitic because it depends up on female gametophyte.

A taxon (plural taxa; back-formation from taxonomy) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit.

Vascular Cryptogam refers to those vascular plants that do not make seeds, for example, Pteridophytes.

Ernst Haeckel proposed the three-kingdom system in 1866, adding Protista to the existing Animalia and Plantae kingdoms to include unicellular organisms.

Fungi are heterotrophic organisms that lack chlorophyll and are often referred to as non-green thallophytes. They were separated from the plant kingdom in Whittaker's classification.