Under General Science section, Plant Kingdom is an important chapter for upcoming competitive exams, specially RRB NTPC, SSC, CDS, UPSC etc. In this article we have provided a brief note on “General Characteristics of Bryophytes” along with the economic and ecological importance of Bryophytes and much more info.
Table of Contents
Introduction
• Biologist Robert Whittaker divided the entire living kingdom into five 5 kingdoms – Animalia, Plantae, Fungi, Protista, and Monera.
• Among the 5 groupings the plant kingdom or kingdom Plantae has been classified into five subgroups.
1. Algae
2. Bryophyta
3. Pteridophyta
4. Gymnosperms
5. Angiosperms
• The taxonomic group Plantae includes all plants and green algae on the Earth.
• In this article we give you a brief overview about the Characteristics of Bryophytes of Kingdom Plantae.
About Bryophyte
• The Bryophytes are those embryophyte plants (‘land plants’) that are non-vascular. They have tissues and enclosed reproductive systems, but they lack vascular tissue. They neither flower nor produce seeds, reproducing via spores.
Study of Bryophyte: Bryology
Father of Bryology” F. Cavers
Father of Indian Bryology: S.R Kashyap
Term Bryophyta coined by Braun.
General Characteristics of Bryophytes
• Bryophyta is most primitives and simplest embryophyte.
• They belong to atracheophyta that is lacking of vascular bundles
• In Bryophyta the haploid generation is independent and dominant.
• Most of the Bryophyta are terrestrial, but a few are aquatic.
• The Bryophytes are commonly called Moss.
• They are commonly known as Amphibians of the plant kingdom, because these plants can live in the soil, but are dependent on water for sexual reproduction.
• These are first terrestrial land plants.
Structure of Bryophyte
• The plant body of bryophytes is more differentiated than that of algae.
• It is thallus-like and prostrate or erect.
• They lack true roots, stem or leaves.
• They may possess root-like, leaf-like or stem-like structures.
• The main plant body of the bryophyta is haploid.
◘ What is Thallus (plural: thalli) like structure?
- Thallus means a flat body with no differentiation into roots, stem and leaves.
- Just remember the word “Thali or Thela” which means Plate or dishes, and a plate contains the only circular body. They don’t have legs (roots) or head (Stem and leaves).
Reproduction in Bryophyta
• Bryophyta produces gametes, hence is called a gametophyte.
• The sex organs in bryophytes are multicellular.
• The male sex organ is called antheridium.
• The female sex organ is called archegonium.
• The male sex organ produces biflagellate antherozoids.
• The female sex organ is flask-shaped and produces a single egg.
• The antherozoids are released into water where they come in contact with archegonium. An antherozoid fuse with the egg to produce the zygote.
• Zygotes produce a multicellular body called a sporophyte. The sporophyte is not free-living but attached to the photosynthetic gametophyte and derives nourishment from it.
• Some cells of the sporophyte undergo reduction division (meiosis) to produce haploid spores. These spores germinate to produce gametophyte.
Habitat of Bryophyta
• Most of the bryophyta are terrestrial nonvascular plants.
• They usually occur in damp, humid, moist and shaded localities.
Example of Aquatic Bryophyta
- Floating crystalwort (Riccia fluitans)
- Fringed heartwort (Ricciocarpus)
- Riella
Example of Saprophytic Bryophyta
- Bug moss or elf-cap moss (Buxbaumia aphylla)
- Cryptothallus Mirabilis
Example of Epiphytic Bryophyta
- Frullania sps.
Example of Xerophytic Bryophyta
- Polytrichum
- Tortula
Fact about Bryophyta
• Largest Bryophyta – Dawsonia (Fontinalis)
• Zoopsis is the Smallest Bryophyta.
• First recorded fossil bryophytes were Hepaticites.
• The golden mine of Liverworts is found in the Western Himalayas.
• Liverworts are Lower thalloid bryophytes.
• It has 24000 species.
Structure of Bryophytes
• Like algae, its main plant body is thalloid-shaped (plant body Not differentiated into root, stem and leaves), but more differentiated than that of algae.
• Some time They may possess root-like, leaf-like or stem-like structures, but They lack true roots, stem or leaves.
. Plant body differentiated into stem and leaf like structures.
• In place of roots unicellular or multicellular hair like Rhizoids are present.
• In Bryophyta the vascular bundles are absent.
• Haploid generation dominant.
• The male sex organ is known as Antheridium
• The female sex organ is known as Archegonium.
Similarities of Bryophyta with Algae
• Both Algae and Bryophyta are having a female reproductive organ, Archegonia.
• Flagellate male gamete.
• Water is essential for fertilization.
• Both Bryophyta and Algae have Thalloid like pant body
• Gametophytic generation present in both Bryophyta and Algae.
• Both have no roots.
• Vascular bundles absent in both Algae and Bryophyta.
• Stored food: Starch
Differences between Algae and Bryophytes
| Algae | Bryophyta |
|---|---|
| Most of the algae are aquatic | Most of the Bryophyta are terrestrial. |
| No division of labour in the algae | Division of labour is seen in the Bryophyta. |
| In algae sexual reproduction may be Isogamous, Anisogamous and Oogamous | In Bryophyta it is always oogamous. |
| In algae unicelled sex organ not surrounded by the sterile jacket layer | In Bryophyta the multicelled sex organ surrounded by the sterile jacket layer. |
| In algae the embryo is not formed | in Bryophyta the embryo is formed |
Difference between Bryophyta and Pteridophyta
| Bryophyta | Pteridophyta |
|---|---|
| In Bryophyta the Gametophytic generation is dominant | In Pteridophyta sporophytic generation is dominant. |
| The pant body of Bryophyta may be thalloid or foliose | In Pteridophyta the plant body differentiates into root, Stem and Leaves. |
| Bryophyta are nonvascular plants | Pteridophyta are vascular plants. |
Ecological and economic importance of Bryophytes
• The economic importance of Bryophytes is very less; here are some of the most common uses of Bryophytes
Fodder
• Some mosses provide food for herbaceous mammals, birds and other animals.
In Gardening materials
• Because of its high water retention capacity, it is used in seedbeds, seedling tray, greenhouses and nurseries to root cuttings and also used as a soil mixture.
• Sphagnum is also used to maintain high soil acidity required by certain plants
Fuel and Packing Materials
• Sphagnum, a species of moss, provides peat that has long been used as fuel.
• Due to high water holding capacity, it also used as packing material for trans-shipment of living.
In research
• Mosses and liverwort use in genetic research. The mechanism of sex determination in plants was discovered in the liverwort
Ecological importance
• Mosses along with lichens formed colonize on rocks. They decompose rocks making the substrate suitable for the growth of higher plants.
• Since mosses form dense mats on the soil, they reduce the impact of falling rain and prevent soil erosion.
Medicinal uses
• Sphagnum moss is used in surgical dressings due to its high absorbency and some antiseptic properties to fill absorbent bandages in cotton swabs to exfoliate boils and wounds.
• Merchantia is a species of liverwort used to treat pulmonary tuberculosis and liver problems.
• Decoction of dried sphagnum is used to treat acute bleeding and eye infections.
• Peat-tar is antiseptic and used as a preservative.
• Sphagnol, which is a distillate of peat-tar is used to treat skin disease.
• Polytrichium species has shown to dissolve stone in kidney and gall bladder.
• Antibiotics can be extracted from some bryophytes with antibiotic properties.
Different types of Bryophytes
• The Bryophytes are divided into three groups they are
- Liverworts
- Mosses
- Hornworts
• According to the NCERT, Here we only discuss about the liverworts and mosses.
Liverworts
• The liverworts grow usually in moist, shady habitats such as banks of streams, marshy ground, damp soil, bark of trees and deep in the woods.
• The plant body of a liverwort is thalloid.
• Asexual reproduction in liverworts takes place by fragmentation of thalli, or by the formation of specialized structures called gemmae.
Common examples of Liverworts
• Marchantia
Mosses
- Mosses have the ability to reproduce in a variety of ways that can be classified as sexual and vegetative.
- Mosses are small, non-vascular flowerless plants.
- They belong to the group Bryophyta.
- Mosses typically form dense green clumps or mats.
- They consist of upright, slender axes bearing spirally arranged leaves.
- Mosses are often found in damp or shady locations.
- The plant body, usually composed of simple leaves that are generally only one cell thick.
- The plant body attached to a stem that may be branched or unbranched.
- They are attached to the soil through multicellular and branched rhizoids.
- The tallest moss in the world is ‘Dawsonia’.
Common examples of mosses
• Funaria
• Polytrichum
• Sphagnum
Primary source of the Article NCERT Class 11
