· Bryophytes are cryptogams (i.e. they don't bear flowers or seeds) or flowerless or seedless plants.
Classification of Bryophyta
Class I: Hepaticae or thalloid Liverworts. eg. Riccia, MarchantiaClass II: Anthocerotae or Horned Liverworts or Hornworts eg. Anthoceros
Class III: Musci or Mosses eg. Funaria, Polytrichum.
· Study of Bryophyte: Bryology
· Father of Bryology: Hedwig
· Term Atracheophyte was used for Bryophytes by Oswald Tippo.
· Bryophytes are the first land-inhibiting plants
· These are the first embryophytes and the first plant in the plant kingdom to have a heteromorphic alternation of generation.
· Simplest group of land plants
· Simplest group of land plants
· Vascular tissue (xylem and phloem) is absent.
· The plant body thallus is differentiated into simple leaf and stem.· They lack true roots, stems, and leaves.
· True roots are absent and water is necessary for fertilization so-called amphibians of the plant kingdom.
· Main body is Gametophytic. Gametophytic generation is dominant over the sporophytic generation
· Archegonia are multicellular flask-shaped with neck canal cells, ventral canal cells, and egg.
· Sporophyte which is differentiated into foot, seta, and capsule.
· Neck is made of 6 vertical rows of cells and encloses 4 – 10 Neck canal cells (4 – 6 in Riccia and Marchantia whereas 6 – 10 in Funaria).
· Archegonium of Marchantia is inverted and that of Funaria is erect.
· Below neck canal cells, there is ventral canal cells and egg cell in the venter.
· The wall of the venter divides periclinal to form a protective covering called Calyptra (n) – haploid structure.
· Sexual reproduction is oogamous type.
· Male gamete is motile whereas female gamete is non-motile. Archegonia attract sperm by chemotaxis (due to sucrose in Funaria and potassium/protein in Riccia and Marchantia).
· Sex organs are multicellular and enclosed by a jacket layer.
· Jacket layer is absent in Thallophyta (Algae and Fungi)
· Sex organs are antheridia (male sex organ) and Archegonia (female sex organs)
· Bryophytes show Heteromorphic alternation of generation in which haploid gametophyte is dominant over diploid sporophyte.
· Male gametes are motile and biflagellated.
· After fertilization oospore/zygote (2n) is formed.
· Spores are formed in the capsule after reduction division and are homosporous.
· Spores on germination give rise to the gametophytic body usually through protonema.
· Oospore (zygote) after fertilization forms sporangium (sporophytic body) @ Oosphere means egg cell (n)
Smallest bryophyte – Zoopsis
Largest bryophyte – Dawnsonia
NOTE:
· Bryophytes are mostly terrestrial except few aquatic genera. Eg: Riccia fluitans, Ricciocarpus natans, Fontanalis antipyretica, Riella etc.
· Most of the bryophytes are autotrophic but few are saprophytic eg: Buxbaumia aphylla and Cryptothallus mirabilis.
· True roots are always absent in bryophytes and in place of roots unicellular (eg: Riccia, Marchantia) or multicellular(eg: Funaria) rhizoids are present which performs the function of the root.
· Largest bryophytes: Dawsonia (Australian moss)
· Longest bryophyte: Fontinalis antipyretica (Brook moss)
· Smallest bryophyte: Zoopsis
· Bryophytes are mostly terrestrial except few aquatic genera. Eg: Riccia fluitans, Ricciocarpus natans, Fontanalis antipyretica, Riella etc.
· Most of the bryophytes are autotrophic but few are saprophytic eg: Buxbaumia aphylla and Cryptothallus mirabilis.
· True roots are always absent in bryophytes and in place of roots unicellular (eg: Riccia, Marchantia) or multicellular(eg: Funaria) rhizoids are present which performs the function of the root.
· Largest bryophytes: Dawsonia (Australian moss)
· Longest bryophyte: Fontinalis antipyretica (Brook moss)
· Smallest bryophyte: Zoopsis
1. HEPATICOPSIDA (Hepaticae)
· Prostrate body structure with unicellular rhizoids.
· Members are commonly called Liverworts (lower bryophytes)
· Gametophytic plant body and is dorsoventrally flattened and dichotomously branched.
Eg: Marchantia, Riccia
Marchantia
· Marchantia is a rosette type of thalloid liverwort showing conspicuous dichotomous branching with a distinct midrib.· Marchantia grows on damp and old walls and spreads rapidly during the rainy season forming a sort of green carpet.
· Marchantia is dioecious i.e. having male and female reproductive organs in separate individuals.
· Plant body is dorsoventrally flattened and Dichotomously branched.
· Dorsal surface contains Midrib and Gemma cups.
· Ventral surface contains Rhizoids and scales.
· Unicellular rhizoids are found in Marchantia and fern prothallus.
· Multicellular rhizoids are in funaria.
· Plant body of Marchantia is dioecious (unisexual)
· Unicellular rhizoids found in Marchantia are of two types
(a) Smooth wall rhizoids: They help in penetration.
(b) Tuberculate Rhizoids: It helps conduct water and minerals.
· Scale (Ligulate and appendicular) helps in the protection of the apical notch (has a single dividing cell).
· Vegetative reproduction by – fragmentation, Gemma and decay of the old basal portion of the thallus which separates to form a branch.
· Gemmae is developed inside the gemma cup and a single gemma can form two Marchantia thalli.
· Sexual reproduction is by the fusion of Archagonia and Antheridia.
· Archegonia develops in archegoniophore (female branch) with a star-shaped or umbrella-shaped disc or receptacle with radiating rays or arms.
· Archegonium of Marchantia is inverted and covered by a membrane called perichaetium.
· Antherozoids are developed in Antheridiophore (male branch), with a more or less circular disc or receptacle on the top.
· After fertilization, the zygote is formed which later changes to sporogonium.
· Sporogonium is differentiated into the foot (helps in absorption), seta. (a short stalk that helps in conduction) and capsule (helps in spore formation)
Capsule contains
(i) Spores (n) – formed after meiosis
(ii Elaters (2n) – formed directly from sporophytic tissue, which helps in the dispersal of spores.
(iii) Calyptra (remanant of ventre)
· The young sporogonium is surrounded by three protective layers calyptra (the innermost 2 layered), perigynium (middle one-celled thick), and perichaetium (the outer one).
2. ANTHOCEROTOPSIDA
· Known as “Hornworts” or “horned liverworts”.
· The gametophytic plant body is thallose which is dorsoventrally differentiated and dichotomously branched.
· Unicellular and smooth-walled rhizoids are present. Tuberculated rhizoids and multicellular scales are altogether absent.
· Pseudoelaters are present in the capsule.
· Dehiscence of the capsule is irregular
(a) Smooth wall rhizoids: They help in penetration.
(b) Tuberculate Rhizoids: It helps conduct water and minerals.
· Scale (Ligulate and appendicular) helps in the protection of the apical notch (has a single dividing cell).
· Vegetative reproduction by – fragmentation, Gemma and decay of the old basal portion of the thallus which separates to form a branch.
· Gemmae is developed inside the gemma cup and a single gemma can form two Marchantia thalli.
· Sexual reproduction is by the fusion of Archagonia and Antheridia.
· Archegonia develops in archegoniophore (female branch) with a star-shaped or umbrella-shaped disc or receptacle with radiating rays or arms.
· Archegonium of Marchantia is inverted and covered by a membrane called perichaetium.
· Antherozoids are developed in Antheridiophore (male branch), with a more or less circular disc or receptacle on the top.
· After fertilization, the zygote is formed which later changes to sporogonium.
· Sporogonium is differentiated into the foot (helps in absorption), seta. (a short stalk that helps in conduction) and capsule (helps in spore formation)
Capsule contains
(i) Spores (n) – formed after meiosis
(ii Elaters (2n) – formed directly from sporophytic tissue, which helps in the dispersal of spores.
(iii) Calyptra (remanant of ventre)
· The young sporogonium is surrounded by three protective layers calyptra (the innermost 2 layered), perigynium (middle one-celled thick), and perichaetium (the outer one).
2. ANTHOCEROTOPSIDA
· Known as “Hornworts” or “horned liverworts”.
· The gametophytic plant body is thallose which is dorsoventrally differentiated and dichotomously branched.
· Unicellular and smooth-walled rhizoids are present. Tuberculated rhizoids and multicellular scales are altogether absent.
· Pseudoelaters are present in the capsule.
· Dehiscence of the capsule is irregular
E.g. Anthoceros.
3. BRYOPSIDA (Musci)
· They are higher bryophytes.
· Leaves are spirally arranged.
· Gametophytic plant body is erect and differentiated into stem-like and leaf-like structures.
· Rhizoids are unicellular.
· Spores form filamentous protonema which gives rise to a gametophyte.
E.g. Funaria (cord moss),
3. BRYOPSIDA (Musci)
· They are higher bryophytes.
· Leaves are spirally arranged.
· Gametophytic plant body is erect and differentiated into stem-like and leaf-like structures.
· Rhizoids are unicellular.
· Spores form filamentous protonema which gives rise to a gametophyte.
E.g. Funaria (cord moss),
Polytrichum (Hair cap moss),
Sphagnum (Peat moss or Bog moss)
Funaria (Moss plant)
The systematic position of FunariaKingdom: Plantae
Subkingdom: Embryophyta
Phylum: Bryophyta
Class: Bryopsida (Musci)
Subclass: Bryidae
Order: Funariales
Family: Funariaceae
Genus: Funaria
Funaria is also called common moss or green moss or cord moss.
The plant body is gametophytic(n). There are two forms of it:
i. Algae-like branched filamentous portion called protonema which is produced by germination of spores. It is ephemeral or short-lived.
ii. Somewhat erect portion of protonema near the substratum, containing chlorophyll is chloronema whereas the deep portion, branched with oblique septa is the rhizoidal portion (non-green and multicellular).
· These most commonly occur in old damp walls, the trunk of frees and on damp ground during the rainy season.
· Often called cord moss.
· Occur most commonly on log dump walls, tree trunks and on damp ground during the rainy season.
· True roots are absent but the plant bears a number of slender multicellular branching threads called rhizoids which perform the function of the root.
· Moss plant represents gametophyte and sporogonium represents sporophyte generation.
· Moss plant may be monoecious or dioecious.
· Plant body is differentiated into Rhizoids (multicellular), Axis and leaf. (@Axis and leaf are false structures because they lack vascular tissue.)
· Vegetative reproduction is by Gemma, Tuber.
· Vascular tissue (xylem and phloem) is absent.
· The plant body thallus is differentiated into simple leaf and stem.
· They lack true roots, stems and leaves.
· True roots are absent and water is necessary for fertilization so-called amphibians of the plant kingdom.
· Main body is Gametophytic. Gametophytic generation is dominant over the sporophytic generation
· Archegonia are multicellular flask-shaped with neck canal cells, ventral canal cells and egg.
· Sporophyte which is differentiated into foot, seta and capsule.
· Neck is made of 6 vertical rows of cells and encloses 4 – 10 Neck canal cells (4 – 6 in Riccia and Marchantia; 6 – 10 in Funaria).
· Archegonium of Marchantia is inverted and that of Funaria is erect.
· Below neck canal cells are venter canal cells and egg cells in the venter.
· The wall of the venter divides periclinally to form a protective covering called Calyptra (n) – haploid structure.
· Sexual reproduction is oogamous type.
· Male gamete is motile whereas female gamete is non-motile. Archegonia attract sperm by chemotactic (due to sucrose in Funaria and potassium/protein in Riccia and Marchantia).
· Protonema is the Juvenile stage of the moss plant, which is a green filamentous algae-like structure with oblique septa.
2 types:
A. Primary protonema
· It is a green filamentous stage in the development of gametophyte which is directly developed from spore.
2 types:
A. Primary protonema
· It is a green filamentous stage in the development of gametophyte which is directly developed from spore.
B. Secondary protonema
· Protenema formed from any other means except the germination of spore. They may develop from the fragmentation of primary protonema wounded portion of leaf shoot or marginal cells of rhizoids or any other vegetative structure.
· Sexual reproduction is by the formation of antheridia and archegonia.
· Archaegonium is erect and paraphyses are present in between archegonia.
· Paraphysis is a multicellular hair-like structure that is present in between archegonia and antheridia. Paraphysis develops a rounded structure at the top in the case of antheridium but the rounded structure is absent in the case of the archegonium.
· Presence of perigoneal and perichaetial leaves. Perigoneal leaf surrounds antheridium and perichaetial leaf surrounds archegonia.
· After fertilization zygote or oospore (2n) changes into sporogonium.
· Sporogonium grows as a semi-parasite on the moss plant
· Sporgonium of funaria contains foot, seta and capsule.
· Seta is elongated and the capsule is differentiated into Apophysis Theca and operculum.
· Stomata (chloroplast-containing cells) are present in the apophysis region of the capsule. These stomata contain single circular guard cells.
· Sterile part of the moss capsule is called columella which contains water and food.
· Columella is found in moss capsule mucor and Rhizopus which helps in the conduction and storage of foods.
· Peristome is the teeth-like hygroscopic structure, that helps in the dispersal of spores.
· Operculum is the circular cap-shaped lid at the top of the capsule.
· Annulus is the ring-like layer of thickened cells at the base of the operculum.
· Calyptra – Cap-like structure that covers capsule.
· Sporophytic body of funaria is partially independent of the gametophytic body.
 |
Fig: Showing life cycle of funaria |
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Fig: L.s of capsule of funaria. |
Examples of True mosses
Funaria – Cord moss
Polytrichum – hair cap moss
Sphagnum – peat or bog moss
Funaria – Cord moss
Polytrichum – hair cap moss
Sphagnum – peat or bog moss
Examples of False moss
1. Lichen: Reindeer moss (Cladonia), Iceland moss (Cetraria), Wolf moss (Letharia)
2. Red algae: Irismoss or sea moss or carrageen (Chondrus)
3. Pteridophyte: Club moss (Lycopodium), spike moss, Bird's nest moss (Selaginella)
· Spanish moss (Tillandsia) is an epiphytic angiosperm.
· Monoecious gametophyte is found in Funaria and Dryopteris.
· The dehiscence of the moss capsule takes place by the rupture of the annulus.
· Moses are the indicators of soil pollution.
· Sphagnum and other Moses are the sources of the pit. So sphagnum is called peat moss.
2. In broyophyte the archegonium consists of venter and egg. The venter has VCC and NCC. At maturity VCC and NCC [4-6 In Riccia and Marchantia (@ 46RIMA) and 6-10 in Funaria disappears and the male gamete fuses with the egg to form Zygote/oospore (2n). The oospore later forms sporangium (sporophytic body). But, Oosphere means egg so is haploid (n).
3. The oospore represents the 1st stage of sporophytic generation which divides to form foot, setae, and capsule. The capsule has sporogenous mass and Elaters (HYDROCHASY). The dorsal wall of Venter forms Calyptra.
4. So, oosphere = n
Elaters = 2n
Calyptra = n (Remnant of venter)
5. In Marchantia the sporangium is surrounded by three protective layers: Calyptra (innermost 2 layered, perigynium (middle one, thickened. Perichaetium (outer sac)
6. In the bryophyte life cycle is haploid-diplobiontic [@haploid (gametophytic or plant body) is more dominant than diploid (sporophytic)]
7. Sex organs are biflagellated.
8. Marchantia is dioecious while Funaria is monoecious (@ MAD CYCAS), Marchantia and cycas are dioecious (unisexual)
8. Archegonium of Marchantia is inverted and of Funaria is erect.
9. Sex organs are jacketed, unlike thallophytes which have unjacketed ones.
10. Unicellular rhizoids are present in Marchantia and fern prothallus whereas Multicellular rhizoids are in Funaria.
12. Bryophytes:
Longest: Fontalis
Largest: Dawsonia [@ LoLAFODA]
Smallest: Zoopsis.
1. Lichen: Reindeer moss (Cladonia), Iceland moss (Cetraria), Wolf moss (Letharia)
2. Red algae: Irismoss or sea moss or carrageen (Chondrus)
3. Pteridophyte: Club moss (Lycopodium), spike moss, Bird's nest moss (Selaginella)
· Spanish moss (Tillandsia) is an epiphytic angiosperm.
· Monoecious gametophyte is found in Funaria and Dryopteris.
· The dehiscence of the moss capsule takes place by the rupture of the annulus.
· Moses are the indicators of soil pollution.
· Sphagnum and other Moses are the sources of the pit. So sphagnum is called peat moss.
High Yielding Points from Bryophytes
1. Paraphysis is distinctly found in Funaria and perichaetium is found in Marchantia.2. In broyophyte the archegonium consists of venter and egg. The venter has VCC and NCC. At maturity VCC and NCC [4-6 In Riccia and Marchantia (@ 46RIMA) and 6-10 in Funaria disappears and the male gamete fuses with the egg to form Zygote/oospore (2n). The oospore later forms sporangium (sporophytic body). But, Oosphere means egg so is haploid (n).
3. The oospore represents the 1st stage of sporophytic generation which divides to form foot, setae, and capsule. The capsule has sporogenous mass and Elaters (HYDROCHASY). The dorsal wall of Venter forms Calyptra.
4. So, oosphere = n
Elaters = 2n
Calyptra = n (Remnant of venter)
5. In Marchantia the sporangium is surrounded by three protective layers: Calyptra (innermost 2 layered, perigynium (middle one, thickened. Perichaetium (outer sac)
6. In the bryophyte life cycle is haploid-diplobiontic [@haploid (gametophytic or plant body) is more dominant than diploid (sporophytic)]
7. Sex organs are biflagellated.
8. Marchantia is dioecious while Funaria is monoecious (@ MAD CYCAS), Marchantia and cycas are dioecious (unisexual)
8. Archegonium of Marchantia is inverted and of Funaria is erect.
9. Sex organs are jacketed, unlike thallophytes which have unjacketed ones.
10. Unicellular rhizoids are present in Marchantia and fern prothallus whereas Multicellular rhizoids are in Funaria.
11. Embryogenic development of bryophyte occurs in sporogonium but sporophyte development occurs in archegonium.
At first, the gametes from gametophyte fuses and zygote formed develop into an embryo in sporogonium. Later the development of sporophyte from embryo occurs in archegonium.
12. Bryophytes:
Longest: Fontalis
Largest: Dawsonia [@ LoLAFODA]
Smallest: Zoopsis.
Also, Read Notes of Other Lessons on Botany: