bryopsida general characters in detail.ppt

describes the general characters of bryopsida in clear and lucid manner

1. Bryopsida

2. GeneralCharacters:
1.Itisthelargestclassinbryophytaandincludesabout700generaand
14,000species.
2.Themainplantbodyisgametophyticandcanbedifferentiatedinto
twostages-juvenilestageandleafystageorgametophore.
3.Juvenilestageisrepresentedbygreen,filamentousbranched
structurescalledprotonema.Itdevelopsfromthegerminationofthe
spore.
4.Gametophoresareerectleafybrancheswhichdeveloponthe
protonema.
5.Gametophorescanbebranchedorun-branchedandcanbe
differentiatedintothreepartsrhizoids,stemandleaves.
6.Branchesarisebelowtheleaves.
7.Leavesarewithmidrib,un-lobedandarrangedspirallyinthreetoeight
rowsontheaxis.
8.Rhizoidsaremulticellular,filamentous,branchedwithobliquesepta.

3. 9.Theaxisisdifferentiatedintocentralconductingstrandenclosedby
cortex.
10.Thesexorgans(antheridiaandarchegonia)developfromthe
superficialcellsofthegametophore.
11.Thesporophyteisgreeninearlystagesandcanbedifferentiatedinto
foot,setaandcapsule.
12.Thesetaisusuallyelongated.
13.Thecapsularwallremainsinterruptedbystomataatseveralplaces.
14.Columellaisusuallypresentandendothecialinorigin.
16.Elatersareabsent.
17.Dehiscenceofcapsuletakesplacebyseparationoflidor
operculum.
18.Peristomehelpsinthedispersalofspores.
19.Sporesongerminationproducetheprotonema.

4. Classification
•The class Bryopsida (Musci) has been divided into three sub-classes
(1) Sphagnobrya(Sphagnidae); (2) Andreaeobrya(Andreaeidae), (3) Eubrya
(Bryidae).
I. Sub-class:Sphagnobrya:
•The sub-class has a single order, the Sphagnalesand a single family, the
Sphagnaceae. (Single genus Sphagnum with 326 species).
The characteristic features:
1. They are called 'bog mosses' or 'peat mosses'.
2. The protonemais broad and thalloseand it produces one gametophore.
3. The leaves or gametophores lack mid-rib and usually composed of two
types of cells-the narrow living green cells and large hyaline dead cells.
3. The branches arise in lateral clusters in the axis of the leaves.
4. The antheridia are borne in the axis of leaves on the antheridialbranch.
5. The archegonia are terminal.
6. The sporogenoustissue of a sporophytedevelops from the amphithecium.
7. The sporogoniumremains elevated above the gametophyte.

5. II.Sub-class-Andreaeobrya:
•Thissub-classhasasingleorder,theAndreaeales,andasinglyfamily,
theAndreaceceae.
•TheimportantgenusisAndreaea.
Thecharacteristicfeatures:
1.Thegametophoresarebrittle,andcaneasilybebroken.
2.Thereispracticallynotissuedifferentiationinplantbody.
3.Theleavesaregenerallylarge,erectandconvolute.
4.Thearchesporiumandcolonmelladevelopfromtheendothecium.

6. III.Sub-classEubrya
•650genera;14,000species
•Thissub-classhasbeenfurtherdividedintofifteenorders.
•Thetruemossesareincludedinthissub-class.
Thecharacteristicfeatures:
1.Theleavesofthegametophoresaremorethanonecellinthickness
andpossessmidribonthem.
2.Theprotonemaisfilamentous.
3.Thesporophytebearsawelldifferentiated,elongatedsetawhich
pushesoutthecapsulefromthegametophore.
4.Thesporogenoustissueisderivedfromtheendothecium.
5.Thearchesporiumdoesnotoverarchthecolumella;
6.Thecolumellacontinuesuptotheapexofthecapsule;bothcolumella
andarchesporiumhavebeenderivedfromtheendothecium.

7. •Order-Sphagnaleshave single genus Sphagnum, which occupies a very
distinct and isolated position among mosses.
1. The plants occur in large patches of a pale green or reddish colour.
2. Their growth has played a large part in the formation of peat.
3. The species are distributed in temperate and arctic climates, but in the
tropics only occur at high levels.
4. The protonemaforms a flat, lobed, thalloidstructure attached to the
soil by rhizoids.
5. The main shoot bears numerous branches which appear to stand in
whorls.
6.Theleaveshavenomidrib.
7.Theantheridiaareglobularandhavelongstalks.
10.Thearchegonialgroupsoccupytheapicesofshortbranches.
11.Thecapsule,thewallofwhichbearsrudimentarystomata,hasa
smalloperculumbutnoperistome.

8. IntroductiontoSphagnum
•Sphagnumispopularlyknownasbogmoss,peatmossorturfmoss
becauseofitsecologicalimportanceinthedevelopmentofpeator
bog.
•Theplantsareperennialandgrowinswampsandmoisthabitat.
•Theygrowalongthebankoflakes.
•Graduallyencroachcompletelycoverupthelake-bog.
•Waterofbogsbecomesveryacidic.
•UpperportionoftheSphagnumgametophoresgrowsindefinitely,
whilethebasalpartdiesprogressively.
•Thedeadplantpartsdonotdecomposeeasilyinacidicsoil.
•Consequentlyalargemassofdeadremainsaccumulatedyearafter
yearfollowedbycompressionfromplantsontop,thusacompact,
darkcolouredsubstancerichincarbonisformedwhichisknownas
peat.
•SinceSphagnumisthechiefconstituentofpeat,itisoftencalledpeat
moss.

10. StructureofSphagnum:
A.ExternalFeatures:
B.ThegametophytephaseofSphagnumisrepresentedbytwodistinct
stagesnamely,
C.(a)juvenileprotonema,and(b)matureleafyorgametophorestage.
D.Thematureplantsgrowindenseclumpsandtheirshootsareof
whitishorbrownishgreenincolour.
E.AllspeciesofSphagnumaccumulateswaterandoftengrowwith
brightcolour(deepred,rosepink,etc.)duetothepresenceofwater-
solublepigments,anthocyanin.
F.Theyareperennialshowingunlimitedgrowthbymeansofanapical
cellwiththreecuttingfaces.
G.Veryyounggametophytesbearmulticellularrhizoidswithoblique
septa.
H.Maturegametophytes,however,donotbearrhizoids.
I.Itisdifferentiatedintoanuprightbranchedaxisandleaves.

11. StructureofSphagnum:
A.MainAxisandBranches:
•Themainaxisissoftandweakatyoungstage,butbecomeserectand
stoutatmaturity.
•However,themainaxisismuchlongerinaquaticspecies,butis
relativelyshortinterrestrialform.
•Theaxisbranchesprofuselyonthelateralsides.
•Singlebranchorintuftsof3to8branchesarisefromtheaxilsof
everyfourthleafofthemainaxis.
•Attheapexofthemainstem,manysmallbranchesoflimitedgrowth
aredenselycrowdedformingacompactheadcalledcoma.
•Thecomaisformedneartheapexduetothecondensedgrowthof
apicalinternodes.
•Asthestemgrowsinlengththeseshortbrancheselongateand
becomenormalbranches.

13. •Thesubmergedspecies(S.obesum,S.cuspidatum)haveallthe
branchessimilarinformandstructure,
•Terrestrialspeciesproducetwotypesofbranchesviz.,
•(i)pendentbranches,and(ii)upwardlydivergentbranches
PendentBranches:
•Thesearelongslenderlooselyarranged,turndownwardsandthen
growparalleltothemainaxis.
•Theyarealsotermedflagellaformorde-currentbranches.
DivergentBranches:
•Theseareshortandstoutbrancheswhichgrowoutwardsand
upwards.
•Theyarealsotermedex-currentbranches.
•Sometimes,onedivergentbranchineachnodedevelopsstronglythan
othersandultimatelygivesrisetoanewplantwhenitbecomes
detachedfromthemotherplant.

15. Leaves:
•Theleavesoccurbothonthemainaxisaswellasonthebranches.
•Onthebranches,theleavesarecloselysetand,therefore,overlapping
andareplacedapartonthemainaxis.
•Theleavesarearrangedinspiralphyllotaxy.
•Moreover,theleavesonthemainaxisdifferfromthoseonthe
branchesinsize,shapeanddetailsofcellstructure.
•Ingeneral,theleavesaresmall,sessile,entire,thinandscale-likewith
acuteapexandwithoutamidrib.

17. B.InternalStructure:
•Stem:Internally,thestemshowsthreezones
(a)OuterCortex:
•Thecortexorthehyalodermisistheoutermostregionofthestem.
•Thisisboundedexternallybyasingle-layeredepidermis.
•Itiscomposedoflargehyalinecells.
•Thegenus,Sphagnumhasoftenbeendividedintotwosub-generabased
onthenatureofhyalinecells.
(b)MiddleHadrom:
•Itliesnexttothecortexandconsistsof4-6layersofsmallthick-walled,
prosenchymatouscells.
•Thispartiscalledhadromwhichgivesmechanicalsupporttothestem.
(c)CentralCylinderorMedulla:
•Itistheinnermostregionofthestem,comprisedofsmall,vertically
elongated,thin-walledparenchymatouscells.
•Itfunctionsasstorageregion.

19. Leaf:
•InSphagnum,thecross-sectionofleafshowsonlyonecellinthickness
andcomposedofmuchelongatedcells.
•Ayoungleafiscomprisedofsquareorrectangularcellsofuniformsize,
whileamatureleafischaracterisedbytwotypesofcells,theordinary
typehyalinecellsandthegreenchlorophyllouscellsortheassimilatory
cells.
•Thehyalinecellsarelargepolygonalandbecomecolourlessorhyalineby
losingtheirprotoplasts.
•Theirwallsareprovidedwithporesandbecomespirallythickened.
•Thehyalinecellshavearemarkablecapacityofabsorptionandretention
ofwater(hencecalledcapillarycells),thusrhizoidsarenotnecessaryin
thematureplants.
•Thechlorophyllouscellsaresmalltriangularorbiconvexlivingcellswith
manydiscoidchloroplastsandhavetheirphotosyntheticability.
•Thechlorophyllousandthehyalinecellsarearrangedinanalternate
sequencetoformaregularreticulatepatternandthisleaf-featurealone
canbeusedtoidentifythegenus,Sphagnum.

23. ReproductioninSphagnum
•InSphagnum,reproductiontakesplaceboth
byvegetativeandsexualmethods.
•Thevegetativepropagationismorecommon:
VegetativeReproduction:
•Vegetatively,itreproducesbymeansof
innovation.
•Sometime,oneofthedivergentbranches
growsupwardsandbecomesasstrongasthe
mainstem.Suchanapicalbranchiscalled
innovation.
•Duetotheprogressivedeathofthelower
basalpartofthemainaxis,theinnovation
getsdetachedfromthemotherplantand
ultimatelygivesrisetoanewplant.
•Thisphenomenonisresponsibleforthe
extensivegrowthofSphagnuminnature.

24. SexualReproduction:
•Sphagnummaybemonoeciousordioecious,
•Antheridiaandarchegoniaarealwaysborneonthespecialseparate
antheridialandarchegonialbranchesofthesameplant.
•Thesebranchesaremuchsmallerthanthevegetativebranches.
•Inmonoeciousplants,theantheridialbranchesdevelopfirst.
AntheridialBranch:
•Theantheridialbranchesfirstappearneartheapexofthemainstem.
•Thesebranchesareusuallyshorterbutstouterthanthevegetative
branches.
•Theyarespindle-shapedanddenselycoveredwithyellow,redor
darkgreenleavesgenerallysmallerthanthefoliageleaves.

25. Sphagnum spp.(A) Antheridial Branch (B) Leaves and Antheridia (L.S. View) (C) Development of
Antheridia (D) Mature Antheridium (E) Antherozoid

26. AntheridiumDevelopmentandStructureofAntheridium:
•Theantheridiadevelopsinglyandacropetallybelowtheleaves.
•Eachantheridiumdevelopsfromasuperficialantheridialinitialofthe
stem.
TheMatureAntheridium:
•Ithasalongstalkoftwotofourrowsofcellsandaglobosebody.
•Thebodyhasajacketofonelayerofcellsenclosingamassofandrocytes
formedfromthespermmothercells.
•Eachandrocytecellmetamorphosesintoaspirallycoiledbiflagellate
antherozoidorsperm.
DehiscenceoftheAntheridium:
•Theapicalcellsofthejacketofamatureantheridiumswellthroughthe
absorptionofwater.
•Asaresultofturgorpressurethusgenerated,thewalloftheswollen
antheridiumbreaksintoanumberofirregularlobesattheapexthat
eventuallyturnsbackwards.
•Themassofandrocytescomesoutandtheantherozoidsareliberated
immediatelyandswimfreelyinwater.

28. ArchegonialBranches:
•Archegoniaareborneattheapicesofthearchegonialbrancheswhich
developattheapex,orlaterally.
•Thearchegonialbranchesareveryshortandmoreorlessovoidin
shape.
•Theleavesonthesebranchesarelargerthanthosepresentonthe
foliageleaves.
•Theupperleavesofthesebranchesconstitutetheperichaetium
enclosingthearchegoniaandthusprotectarchegoniafrominjury.
Archegonium:
Thearchegoniadevelopontheapexofthearchegonialbrancheseither
singlyoringroups.
Theapicalcellofthisbranchformstheprimaryarchegonium.
Twotofivesecondaryarchegoniadevelopfromderivativesoftheapical
cell.
Usually,therearethreearchegoniainagroupi.e.,oneprimary
archegoniumattheapexandtwosecondaryarchegoniaemergefrom
thebaseofprimaryarchegonium.

29. ArchegonialBranches:
•Archegoniaareborneattheapicesofthearchegonialbrancheswhich
developattheapex,orlaterally.
•Thearchegonialbranchesareveryshortandmoreorlessovoidin
shape.
•Theleavesonthesebranchesarelargerthanthosepresentonthe
foliageleaves.
•Theupperleavesofthesebranchesconstitutetheperichaetium
enclosingthearchegoniaandthusprotectarchegoniafrominjury.
Archegonium:
Thearchegoniadevelopontheapexofthearchegonialbrancheseither
singlyoringroups.
Theapicalcellofthisbranchformstheprimaryarchegonium.
Twotofivesecondaryarchegoniadevelopfromderivativesoftheapical
cell.
MatureArchegonium:
Thematurearchegoniumisarelativelylargestructure.Ithasalongstalk,
alongtwistedneckwith8to9neckcanalcells,amassivemultilayered

30. MatureArchegonium:
•Thematurearchegoniumisarelativelylargestructure.
•Ithasalongstalk,alongtwistedneckwith8to9neckcanalcells,a
massivemultilayeredventercontainingaventralcanalcell,andan
egg.
FertilizationofArchegonium:
•Theprocessoffertilizationtakesplaceonlyinthepresenceofwater.
•Theantherozoidsswimfreelyinwaterandreachthearchegonia.
•Atmaturity,theneckcanalcellsandtheventralcanalcelldisorganize
andformapassagefortheantherozoids.
•Theantherozoidsreachnearthearchegoniaattractedchemotactically
andpassintothepassagetoreachtheegg.
•Ultimately,onlyoneantherozoidfuseswiththeeggandformsa
zygote.

31. Sphagnum Spp. (A) Mature Archegonia (B) Three Archegonia on the tip of a branch

32. TheSporophyte:
•Thediploidzygoteisthefirstcellofthesporophyticgeneration.
•Amongthefewarchegoniaonlyoneisdevelopedtoformembryoin
anarchegonialbranch.
StructureoftheMatureSporophyte:
•Thematuresporophyteconsistsofabulbousfoot,aneck-like
inconspicuoussetaandanalmostsphericalblacktodark-brown
capsule.
•Thewholesporophyteiscoveredbythecalyptra.
•Thelowestpartofthecalyptrathatcoversthefootiscalledthe
vaginula.
•Theperichaetialleavesarepresentbelowthesporophyte.
•Theelongatedarchegonialbranchatthebaseofthesporogoniumis
calledpseudopodium.
•Itincreasesinlengthandpushesoutthecapsuleabovethe
perichaetialleavestofacilitatethespreadingofspores.

33. •Thecapsuleinlongitudinalsectionshowsanouterjacketandmiddle
spore-sacwithsporeswhichoverarchesthedome-shapedinner
columella.
•Thecapsulewall(jacket)isseverallayersthick.
•Theoutermostlayerofthejacketisthickwhichbearsseveral
rudimentarynon-functionalstomata.
•Thecircularbiconvexdisc-shapedlid,calledoperculum,ispresentat
thetopofthejacket.
•Theoperculumisdelimitedfromtherestofthejacketbyagrooveof
thin-walledcells,calledtheannulus.

35. Sphagnum: Different Stages in Sporophyte Development

36. DehiscenceoftheCapsule:
•Thecapsuledehiscesonabrightsunnydaybyanexplosive
mechanism.
•Thecapsulewallandcolumellabecomedryandshrivelduetoheat.
•Thisresultsintheformationofalargeairspacebelowthespore-sac.
•Thesphericalcapsulegraduallybecomescylindricaland,therefore,an
overpressureof4-6atmospheresbuildsupinsidethecapsule.
•Underthisconditionitsoperculumburstsopenthroughtheannulus
withanaudiblesound.
•Thesporesarecatapultedupto20cmandreleaseintheair.The
processisknownasair-gunmechanismofsporedispersal.

38. •Eachspore(tetrade)hasadistinct
triradiateridge.
•Thewallofthesporeisdifferentiated
intoanoutersmoothgranularor
papillateexineandaninnerthinintine.
•Sporesmaygerminatewithin2-3daysor
mayremainviablefor4-6months.
•Thesporeonfallingonamoist
substratumgerminatestodevelopa
smallthalloidprimaryprotonema.
•Asinglebudisdevelopedfromthe
marginalcelloftheprimaryprotonema.
•Thebudeventuallydevelopsintoanew
leafygametophyte.

40. Alternation of Generation in Sphagnum

41. • MORPHOLOGY, ANATOMY AND REPRODUCTION OF EUBRYALES
• 1. The main plant body is gametophyticand can be differentiated into two stages-juvenile stage and leafy stage or gametophore.
• 2. Gametophores are erect leafy branches which develop on the protonema. Branched or un-branched and can be differentiated into three parts-
rhizoids, ‘stem’ and ‘leaves’.
• 3. ‘Leaves’ are with midrib, un-lobed and arranged spirally in three to eight rows on the axis or
• 4. Rhizoids are multicellular, filamentous, branched with oblique septa.
• 5. The axis is differentiated into central conducting strand enclosed by cortex.
• 6. Sex organs borne apically in the groups on main ‘stem’ or a branch.
• 7. The sporophyteis green in early stages and can be differentiated into foot, seta and capsule.
• 8. The seta is usually elongated and rigid.
• 9. Columellais usually present and endothecialin origin.
• 10. Archesporiurn(spore forming tissue) is differentiated only in spores.
• 11. Elaters are absent.
• 12. Dehiscence of capsule takes place by separation of lid or operculum.
• 13. Peristomehelps in the dispersal of spores.
• 14. Spores on germination produce the protonema.
• 10.6.1-Funaria Division -Bryophyte Subdivision -MusciClass -Bryopsida Order -FunarialesFamily -FunariaceaeGenus -FunariaPlant body is
gametophyticand consists of two different stages namely: (i) Juvenile stage represented by primary protonemaand (ii) The leafy gametophore
which represents the adult form. The adult gametophyte (gametophore) is differentiated into rhizoids, axis or ‘stem’ and ‘leaves’. Rhizoids arise
from the base of the axis. They are slender, branched, and multicellularand have oblique septa. Axis is 1—3 cm. high, upright, slender and
branched. Each branch is extra axillaryi.e., arise below a leaf. Leaves are sessile, oblong-ovate with entire margin, pointed apex and are arranged
spirally on the branches and ‘stem’. Each ‘leaf’ is traversed by a single mid rib. ‘Leaves’ are borne in 1/3 phyllotaxywhich becomes 3/8 at
maturity.

43. Funaria Plant and Leaf

44. •(ii) Internal Structure:
•1. Axis or ‘stem’ The transverse section (T. S.) of axis can be
differentiated into three distinct regions: (i) Epidermis (ii) Cortex (iii)
Central conducting strand or central cylinder. (i) Epidermis: It is the outer
most single layered protective covering consisting of small tangentially
elongated chlorophyll bearing cells. Cuticle and stomata are absent. (ii)
Cortex: It is present between the epidermis and conducting tissue. It is
made up to parenchymatouscells. Younger part of the cortex contains
chloroplasts but in the older part they are lacking. At maturity few outer
layers of cortex become thick walled and are reddish brown in colourbut
those of the inner layers become thin walled. (iii) Central Conducting
Strand: It is made up of long, narrow thin walled dead cells which lack
protoplasm. These cells are now commonly called as hydroids.
Conducting strand besides providing a certain amount of mechanical
support, functions in the upward conduction of water and solutes.

45. Transverse Section of Axis

46. •2. Leaf: Transverse section (T. S.) of ‘leaf’
shows a well-defined midrib with two lateral
wings. Except the midrib region, the ‘leaf’ is
composed of single layer of parenchymatous
polygonal cells. The cells contain many large
and prominent chloroplasts. The central part
of the mid rib has narrow conducting strand
of thick walled cells which help in
conduction.

48. •Reproduction in Funaria: Funaria reproduces by vegetative and
sexual methods. Vegetative Reproduction in Funaria: Vegetative
propagation in Funaria is performed by the following methods: (a)
Fragmentation of Primary Protonema: The primary protonema is
developed through the germination of the spore. Under certain
circumstances, it breaks into several fragments. Each detached
fragment bearing buds may grow into a new plant. (b) Secondary
Protonema: The protonema developing from any part of the plant
other than spores is called secondary protonema. Generally, they
are formed on injured rhizoids, stems, leaves or reproductive
structures. They bear buds that are capable of growing into a new
plant (Fig. 6.48B). (c) Bulbil: The bulbils are multicellular, brown,
bud-like structures that develop on the rhizoidal branches. The
bulbils are useful for propagation during unfavourable
environmental conditions by detaching them from the parent
plants. (d) Gemmae: Gemmae (Fig. 6.48B) are multicellular green

50. •Sexual Reproduction in Funaria: Funaria is autociously monoecious,
because the male (antheridium) and female (archegonium)
reproductive structures develop on separate shoots of the same
plant. Antheridia are borne on the main shoot of the plant. The
female branch develops as a side shoot, which grows more
vigorously and becomes longer than the male branches.
Antheridium: The antheridia are borne in clusters at the apex of the
main axis. A number of long multicellular hairs, called paraphyses
are intermingled with the antheridia (Fig. 6.53). Both antheridia and
paraphyses are surrounded by a number of bract-like leaves
forming a rosette called the perichaetium. The paraphyses have
swollen tips (capitate) and contain chloroplasts. Besides their
photosynthetic function, paraphyses protect the young antheridia
against desiccation. The paraphyses assist in the liberation of
antherozoids.

52. •Development of the Antheridium: The antheridium develops from a
superficial antheridial initial located at the tip of the male branch. It
becomes papillose and projects above. It divides by a transverse
wall to form an outer cell and a basal cell. The outer cell divides
further by successive transverse divisions to form a linear filament
of 2 to 4 cells. The terminal cell of the filament divides by two
vertical intersecting walls to form a wedgeshaped apical cell with
two cutting faces. It forms segments in two rows in alternate
sequence. Each young segment of the upper 3 to 4 cells now
divides by a vertically diagonal wall to form two unequal cells. The
smaller peripheral cells are the first jacket initials. While, the
larger sister cell, by a similar division, forms the outer second
jacket initials and the inner primary androgonial cell. The
primary androgonial cell divides and re-divides to form
androcyte mother cells. Each androcyte mother cell divides to
form two androcytes. The androcytes transform into

55. •Archegonium: The archegonia are borne in
clusters at the apex of the archegonial branch.
Development of the Archegonium: A cell at
the tip of the female shoot differentiates into
the archegonial initial. It divides transversely
to form a upper cell and a lower cell. The
upper cell becomes the archegonial mother
cell which divides by two intersecting oblique
walls forming an apical cell with two cutting
faces. The apical cell further divides by three
intersecting oblique walls to form three

56. •Development of the Sporophyte: The zygote
divides transversely to form an upper epibasal
cell and a lower hypobasal cell. Both the
hypobasal and epibasal cells divide repeatedly
to form an young embryo with two growing
points at the two opposite ends, each
representing an apical cell with two cutting
faces. The archegonial wall enlarges and forms
calyptra which covers the capsule till maturity.
A long slender sporophyte is then
differentiated. The capsule differentiates at a

57. •Structure of the Mature Sporophyte: The
mature sporophyte of Funaria is differentiated
into a foot, a long seta and a pear-shaped
capsule at the tip. 1. Foot: It is a poorly
developed conical structure, embedded in the
apex of archegonial branch. 2. Seta: Seta is
long, green in colour when young, but
becomes reddish brown at maturity. T.S. of
seta shows a single-layered epidermis, a
central conducting strand of thin-walled cells
surrounded by a cortex made up of

58. Funaria hygromatica (A) T.S. of Seta (B)
Mature Capsule with Operculum (C) L.S.
of Capsule

61. •(d) Columella: It is the central, axial part of the
fertile zone, comprising of thin-walled,
colourless, compact, parenchymatous cells,
constricted at the base just above the
apophysis. The distal part of the columella is
cone-shaped which projects into the concavity
of the operculum. The columella serves the
purpose of conduction of water and nutrients
to the growing sporophyte. The Apical Region:
The apical region of the capsule is a
complicated structure. This joins the capsule

62. •The whole structure is called peristome which
is epicranoid in nature, because the outer
peristome teeth are superposed on the inner
ring. The tapering distal ends of the outer
peristome teeth are joined to a centrally
placed disc of tissue. Dehiscence of the
Capsule and the Dispersal of Spores: At
maturity, the operculum begins to dry up due
to the non-availability of water supply to the
capsule. Consequently, the thin-walled cells of
the operculum, including the annulus which

63. Life Cycle of Funaria hygromatica

65. Funaria hygromatica: Graphic
Presentation of Life Cycle

67. Polytrichum
Occurrence:
•Polytrichumhaveworldwidedistribution.
•Theyareverycommonincooltemperatureandtropicalregions.
•Plantsliveincoolandshadyplaces.
Generalstructure:
•Themainplantbodyisgametophyte.
•Theadultplantconsistsoftwoparts:rhizomeanduprightleafyshoot.
1.Rhizome:
•Itishorizontalportionandgrowsunderground.
•Itbearsthreerowsofsmallbrownorcolourlessleaves.
•Italsobearsrhizoids.
•Thecellsarerichinprotoplasmandoilglobules.
•Therhizoidsmayarisefrombaseoftheerectgametophores.
•Theyserveasmechanicalfunctionbyprovidingsupportinspeciesin
whichgametophoresgrowstoconsiderableheights.

69. 2.Uprightleafyshoot:
•Theleafyshootsaremuchlonger.
•Itisthemostconspicuouspartoftheplant.
•Itarisesfromrhizome.
•Thesebranchesconsistofcentralaxis.
•Thesebranchesbearlargeleavesarrangedspirally.
3.Leaves:
•Leaveshavebroadbases.
•Leavesintheupperportionaregreen.
•Buttheloweronesarebrown.
•Eachleafhasabroadcolourlesssheathingleafbaseandnarrowdistal
limb.
•Themidribformsthemajorpartoftheleaf.
•Theseleavespossessextraphotosynthetictissueintheformofclosely
setverticalplatesofgreencells.Theseareknownaslamellae.
•Greenlamellaeactasadditionalphotosynthetictissue

70. Theleavesareoftwotypes:
a)Scaleleaves:-
•Thesearesmallbrownoralmostcolourlessleaveswitha
rudimentaryblade.
•Theseoccurinaspiralarrangementaroundthecentralaxis.
b)Foliageleaves:-
•Theseareonlypresentinupperportionofthebranches.
•Eachfoliageleafis6-10mmlongitisdifferentiatedintotheproximal
sheathbaseandthedistaldivergingnarrowlimborblade.
AnatomyLeaf:
•Polytrichumhavecomplexinternalstructure.
•Themid-ribregionisthick.
•Butthemarginsareonlyonecellthick.
•Thelowersurfaceisboundedbyepidermis.
•Oneortwolayersofsclerenchymatoustissuesarepresentabovethe
epidermis.

72. •Thecentraltissueofleafiscomposedofthin-walledparenchymatous
tissues.
•Abovethisareagainsclerenchymatouscells.
•Theuppersurfaceisformedofalayeroflargecellsfromwhicharise
numerouslamellae.
•Thisupperportionisthemainphotosyntheticregionoftheleaf.
Stem:
•TheT.S.ofstemshowsthreeregions:
•medulla,cortexandepidermis.
•Themedullaisagaindifferentiatedintotwozones:centralzoneand
peripheralzone.
•Thecortexconsistsofthick-walledcells.
•Theinnermostlayerofcortexaroundtheconductingstrandsis
knownasamantle.
•Itscellscontainstarchgrain.
•Epidermisispresentoverthecortex.

76. Vegetativereproduction
•Vegetativereproductiontakesplacebyfollowingmethods:
I.Protonema:
•Thesporesgerminatetoformprotonema.
•Severalbudsgrowontheprotonema.
•Eachbudbyofitsapicalcelldevelopsintogametophyte.
2.Buds
•Thesearealsocalledvegetativebuds.
•Theyareformedontherhizoids.
3.Fragmentation:
•Deathorbreakingofshootsseparatestheerectbranches.
•Thesebranchesbehaveasindependentplants.

77. Sexualreproduction
•Polytrichumisdioecious.
•Antheridiaarchegoniaoccurondifferentplants.
Antheridialhead:
•Theantheridiaareborneintheaxillaryclustersatthetipsofleafy
stems.
•Theyaresurroundedbyarosetteofleavescalledperigonialleaves.
•Theperigonialleavesarespirallyarranged.
•Theantheridiaareproducedingroupsintheaxilsoftheseleaves.
•Paraphysesalsooccuramongtheantheridia.
•Matureantheridiumisclubshaped.
•Itiscomposedofashortstalkandaclub-shapedbody.
•Jacketispresentaroundthecapsule.
•Insidethejacketarepresentandrocytemothercells.
•Theygiverisetobiflagellatesperms.

79. Archegonialhead
•Theflask-shapedarchegoniaareborneattheapicesofleafystems.
•Archegoniumissurroundedbyperichaetialleaves.
•Theseleavesoverlaptoformaclosedbud-likestructure.
•Thearchegoniaoccurinclusterof3to6.
•Maturearchegoniumisflask-shaped.
•Ithasathickmulticellularstalk.
•Theneckislongandtwisted.
•Itcontainsneckcanalcells.Theneckconsistsof6-verticalrowsof
cells.
•Neckgraduallymergesintoventer.
•Ventercontainsuppersmallventercanalcellandlowerlargeeggcell.
•Paraphysesareabsent.

81. Fertilization:
•Thesexorgansdehisceinthepresenceofwater.
•Theventercanalcellandtheneckcanalcellsdissolvetoform
mucilage.
•Thismucilageexertspressureandtheneckopensout.
•Themucilagecomesoutoftheneck.
•Thespermsreachedthearchegonialheadsbyrainwater.
•Theyareattractedtowardsthearchegonia.
•Oneofthespermswimsdowntheopenneckandreachesthebase.
•Itfuseswiththeeggtoformoospore.
•Oosporeisthefirststageofsporophyticgeneration.

82. StructureofMatureSporogonium(Sporophyte)
•Thematuresporogoniumisdifferentiatedintofoot,setaandcapsule.
Foot:
•Thefootisburieddeepinthetissueofgametophyte.
•Itisabsorptiveinfunction.
•Itconsistsofthin-wallednarrowcellscontainingdensecytoplasm.
Seta:
•Thesetaisseveralincheslong.
•Itcarriesthecapsulehighintotheair.
•Italsoconductswaterandfood.
•Itconsistsofepidermis,cortexandcentralconductingstrands.
Capsule:
•Theupperpartiscapsulewithquadrangularoutline.
•Itisdifferentiatedintothreeregions:
•apophysis,thecaandoperculum.

85. Apophysis
•Theapophysisisthelowermostpartofthecapsule(alsocalled
theneck).
•Itisabulbous,sterilestructurethatconnectsthecapsulewith
thesetabelow.
•Structurally,theapophysisiscomposedofasingle-layered,
thick-walledepidermis,whichisinterruptedbystomata.
•Thesotmataconsistofasingleringofguardcells.
•Usually,twoguardcellsarepresentineachstoma.
•Belowtheepidermisisthechlorenchyma,consistingofmany
thin-walled,looselyarrangedparenchymatouscells.
•Thereisnohypodermisintheapophysisregion.
•Thecentralpartoftheapophysisiscomposedofnumerousthin-
walledcells,formingaconductingstrand.

86. Theca
•Thethecaisthemiddle,fertileregionofthecapsule.
•Itliesbetweentheapophysisandtheoperculum.
•Alongitudinalsectionofthethecashowsthefollowingregions:
CapsuleWall
•Thecapsulewall,orjacket,isseverallayersthickandcomposedof
parenchymatouscells.
•Theoutermostlayerofthecapsulewallisthesingle-layered
epidermis.
•Itconsistsofcompactlyarrangedcellswiththickouterwalls.
•Theepidermisofthewalllacksstomata.
•Theepidermisisfollowedbytypicallytwolayersofspongy
parenchyma.
•Thecellsofthespongyparenchymaarethin-walledand
chlorophyllous.

87. SporeSacs
•Thesporesacsaresituatedbelowtheouteraircavitiesoneitherside
ofthecolumella.
•Eachsporesachasanouterwallandaninnerwall.
•Bothwallsaremadeupoftwothin-walledcelllayers.
•Thesporesacsarederivedfromthesingle-layeredarchesporium
(sporogenoustissue).
•Thearchesporiumfirstdevelops4-6layersofsporogenouscells.
•Thesporogenouscellsdividetoformmanysporemothercells.
•Thesporemothercellsdividebymeioticdivisionsandformhaploid
spores.
•ThesporesacinPolytrichumissurroundedbyadoubleairspace
system,astheaircavitiesarefoundonbothitsouterandinnersides.

88. AirCavities
•Theaircavities(airspaces)arecylindricalandarepresentonboth
sidesofthesporesacs.
•Theseairspacesaretraversedradiallybydelicatestrands(short
filaments)ofelongatedgreencellscalledtrabeculae.
Columella
•Thecolumellaisthecentralpartofthethecaregion.
•Itismadeupofcompactlyarrangedparenchymatouscells.
•Thecolumellaiscontinuouswiththecentralstrandoftheapophysis
belowandextendsuptotheepiphragmofoperculumabove.
•Columellahelpsintheconductionofwaterandmineralnutrients.

89. Operculum:
•Thisistheuppermostpartofthecapsule.
•Itisconical.Theoperculumiscoveredbycalyptra.
•Thecalyptraformsahairystructure.SoPolytrichumisalsoknownas‘
haircap’moss.
•Aconstrictionispresentbetweenoperculumandtheta.
•Arimordiaphragmispresentatthebaseofthisconstriction.
•Itexpandsintoafan-shapedepiphragm.
•Peristomeispresentintheformofathickrim.
•Itbearsanumberofrigidteeth.
•Theepiphragmfillsthespaceinsidetheringofperistometeethandis
attachedtotheirtips.
•Peristometeetharisefromtherimordiaphragm.

90. •Sporesliefreeinthecentreofthecapsuleatmaturityandcomeout
throughpores.
•Theyaredispersedbywind.
Structureandgerminationofspores
•Thesporesareyellow.
•Eachsporeisuninucleateandhastwowalllayers.
•Theouterlayerisexosporium(exine).
•Theinnerlayerisendosporium.
•Thesporegerminatesunderfavourableconditions.
•Exosporiumrupturesandendosporiumcomesout.
•Itformsprotonema.
•Protonemadevelopsmanybuds.
•Thesebudsproducenewmossplants.
•AlternationofgenerationPolytrichumshowsheteromorphic
alternationofgeneration.

91. •Andreaea Division –Bryophyte
•Subdivision -Musci Class -Andreaeopsida
Order -Andreaeales Family -Andreaeaceae
Genus -Andreaea Andreaea is one of two
moss genera belonging to the class of mosses
known as Andreaeidae and the family
Andreaceae. Andreaeidae, referred to as the
granite mosses, are commonly found on
granite rock faces in mountainous and arctic
regions. Andreaea, a genus comprised of
about 125 species, is the single representative

92. (A) Andreaea rupestris Gametophyte
with Sporophyte (B) T.S. Stem

93. •Sexual Reproduction: Andreaea is homothallic
i.e. monoecious. Antheridia and archegonia
are borne terminally in groups on the separate
branches. A few species for instance A. nivalis
and A. blyttii are heterothallic. Apical cell is
involved in the formation of sex organs.
Antheridia It occurs in the male branch in the
terminal as cluster. The antheridium is
surrounded by a number of male perigonial
bracts. The mature antheridium has an
ellipsoidal or nearly globular body raised on a

94. •wall. Further development is similar to other
mosses and depends on the divisions of apical
cell. Primary stalk cell undergoes repeated
divisions to form the stalk. Archegonia Like the
antheridia, the archegonia arise from surface
cells at the apex of the female branches. A
surface cell protrudes and becomes more or
less papilliform. The first wall formed in it
shows a little variation, but generally it is very
oblique, so cutting off a two-sided apical cell,
as in the antheridium. The variation is in the

95. •The Sporophyte The zygote divides by a
transverse wall. The lower (hypobasal) cell
divides irregularly and forms a haustorial
tissue which later organizes into the foot. The
upper (epibasal) cell is destined to form the
capsule. It first functions as an apical cell with
two cutting faces and soon, after periclinal
divisions, develops an inner endothecium and
an outer amphithecium. The amphithecium
forms the jacket, 3 to 8 cells in thickness. The
inner layers of the endothecium become the

96. Andreaea rupestris (A) Sporophyte (B)
Section of Sporogonial Shoot (C)
Sporangial Shoot bearing Sporophyte

97. •The capsule is easily recognized by its paper-
lantern-like dehiscence. Lacking peristome
teeth, the capsule splits along four
longitudinal slits as a result cell weakness. The
longitudinal valves are responsive to humidity,
which allows the spores to be carried away
when the air is dry and conditions are optimal,
closing when the air becomes moist. This
dehiscence type is a unique characteristic and
occurs exclusively among the granite mosses.
When present, the calyptra is small and

98. Andreaea: (A-E) Germination of Spore
(E) Ribbon like Protonema

99. •MORPHOLOGY, ANATOMY AND
REPRODUCTION OF TAKAKIALES
•It is also a monotypic group having single
family Takakiaceae and single genus Takakia.
The genus is characterized by: 1.
Heterotrichous nature of plants, which are
differentiated into prostrate growing
rhizomatous axis and erect growing aerial axis
or shoot. 2. Both the shoots are densely
covered with mucilage papillae. 3. The leaves
are present in three rows, which are spirally

100. •establishment in 1958 of the species Takakia
lepidozioides, in a new genus Takakia, named
to honor the man who rediscovered it and
recognized its unique characteristics. The
species originally described by Mitten was
subsequently recognized by Grolle as
belonging to this new genus, and accordingly
renamed Takakia ceratophylla. All of the
plants originally collected lacked any
reproductive structures; they were sterile
gametophyte plants. Eventually, plants with

101. Takakia spp. Gametophyte with
Sporophyte

103. •From a distance, Takakia looks like a typical
layer of moss or green algae on the rock
where it grows. On closer inspection, tiny
shoots of Takakia grow from a turf of slender,
creeping rhizomes. The green shoots which
grow up from the turf are seldom taller than 1
cm, and bear an irregular arrangement of
short, finger-like leaves (1 mm long). These
leaves are deeply divided into two or more
filaments, a characteristic not found in any
other moss. Both the green shoots and their

104. •The central strand of the medullary cells is
always surrounded by a single layered cortex
of cells smaller in size. Stem Anatomy: Stem
T.S. shows that it consists of two zones viz.
outer cortical and inner medullary region. The
cortical region is chlorophyllose. It is 1-2
stratose thick and consists of slightly strongly
thick walled cortical cells with brownish wall.
The medullary region shows differentiation
into a small central core of small celled tissue
constituting al ill-defined central strand

105. •All cells of the archegonium, including the egg
cell, are produced by mitosis of haploid
gametophyte cells. The disintegrating neck
and ventral canal cells provide chemicals
involved in sperm chemotaxis to fuse with the
egg. After fusion of egg and sperm, zygote is
formed which is diploid. After fertilization, the
sporophyte grows out of the archegonium,
and nutrients for the developing sporophyte
are provided by the gametophyte.
Sporophyte: The sporophyte has distinct foot,

106. Takakia spp. Sporophyte

107. •The lower part i.e. foot and seta, is protected
by vaginula and the upper part of the capsule
and some part of seta is protected by calyptra.
Capsule is schizocarpous erect, elliptical, green
in early stage of development. Thus
sporophyte is autotrophic in nature. Capsule is
thick in the middle region and symmetrically
tapered at base and apex. Operculum, annulus
and peristome are absent. The outermost
layer of the capsule wall has characteristic
thickening in the cell due to which cell lumen

109. •Characteristic features of the order takakiales
(i) The plant body is differentiated into small,
creeping pale-yellow, leafless rhizome and
erect, green, leafy 1-1.5 cm tall shoot. These
are known as the Gametophores. (ii) Both the
rhizome and the leafy shoots are devoid of
rhizoids. (iii) The thick, fleshly, erect, soft-
textured gametophore axis bears green
leaflike appendages in a 3 -ranked phyllotaxy.
The Leaf -like appendages are small fleshy,
terete and isophyllous. (iv) The leafly

110. Takakia sp. A, Rhizomatous
gametophore
of T. ceratophylla; B. Portion of
gametophore of T.
lepidoziodies with phyllids; C. a single
undivided phyllid;
D, E, F, bifid, trifid and quadrified phyllids
respectively; G,
T.s. Simple Phyllid; H, T.S. Phyllid of
Complex construction,
I. Archegonal short.

111. •ceratopylla was reported from the pool in
Sikkim in Eastern Himalayas ( India).
•Thus both the species grow in cool, moist or
wet shady places at higher altitutes.
•They are hygrophytes.
•4B.1.B STRUCTURE :
•Morphological Structure of Gametophyte -
•The plant body is gametophyte which is
differentiated into a cylindrical,
•branched, creeping, leafless, rhizome-like

112. •more vertically descending leafless branches
which grow downward into the
•substratum. These positively geotropic,
leafless axis is fleshy and soft textured
•The leaf-like appendages borne on the erect
gametophore axis are unique in
•form. They are isophyllous in a spiral manner
from the shoot tip which grows by
•the activity of a 3-sided apical cell. The leaves
are arranged in 3 -ranked phylotaxy.

113. •Slime Papillae -Proskauer (1942) reported the
occurrence of slime papillae on
•the axis of Takakia . These are of two types -(i)
Non -Beaked and (ii) Beaked
•slime Papillae.
•(i) Non -Beaked slime Papillae -These occurs
singly on the erect shoots in or
•near the leaf axils. The non -beaked slime
Papillae in T. ceratophylla cornsists
•of 2-celled short filament. The lower cell

114. Takakia sp. A, Immature beaked open
slime papillae; C, stalked “closed” slime
papillae; D, cells from the leaf primordia
showing chloroplasts & nuclei; E, T.S.
aerial stem.