Characteristics of Bryophytes class 11

Share On Your Social Media

General Characteristics of Bryophytes class 11
General Characteristics of Bryophytes class 11

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

 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

  1. Liverworts
  2. Mosses
  3. 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

 liverwort – Marchantia (a) Female thallus (b) Male thallus
liverwort – 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

Funaria, gametophyte and sporophyte
Funaria, gametophyte and sporophyte

 

Primary source of the Article NCERT Class 11 


Share On Your Social Media

Leave a comment

Ads Blocker Image Powered by Code Help Pro

Ads Blocker Detected!!!

We have detected that you are using extensions to block ads. Please support us by disabling these ads blocker.

Powered By
CHP Adblock Detector Plugin | Codehelppro