Question

What are scales in Riccia?

Answer 1

Hint: Plants without a vascular system consisting of xylem and phloem are known as nonvascular plants. Instead, they may have simpler tissues with specialized functions for water transport within the body. Bryophytes are an informal group that taxonomists now treat as three distinct land plant divisions: Bryophyta (mosses), Marchantiophyta (liverworts), and Anthocerotophyta (anthocerotophyta) (hornworts). Algae, especially the green algae.

Complete answer:
The genus Riccia belongs to the Marchantiales order of liverworts. These plants are small and thalloid, meaning they lack root, stem, and leaf differentiation. The thallus can be strap-shaped and 0.5 to 4 mm wide with dichotomous branches, or it can form rosettes or hemirosettes up to 3 cm in diameter, which can be gregarious and form intricate mats, depending on the species.
Riccia is found in shady spots, damp areas, and other similar terrestrial habitats. Scales are multicellular, single-cell thick structures that are violet in color. Anthocyanin pigment is responsible for the violet color. Scales are usually found on the thallus' ventral surface. They can be arranged in a single row in Riccia's young thallus. Riccia has ligulate scales.
Scales play a role in protecting the growing point by shielding their delicate cells and secreting slime to keep them moist. Scales are absent in some aquatic members of the Marchantiales order, such as Riccia fluitans.
The scales are aligned in a single row along the margin. In hygrophilous species, the scales are ephemeral or short-lived, whereas, in Xerophilous species, the leaves are persistent and leafy. Rhizoids are usually unbranched and unicellular, with smooth or tuberculate walls.

Note:
Rhizoids, on the other hand, are unicellular and unbranched structures in Riccia. They usually come in two types: smooth-walled and tuberculated, and they anchor the plant's thallus to the substrate. These rhizoids can be found in the thallus' mid-rib region.