CONCEPT ON MARCHANTIA

1. MANSI YADAV
SECTION-C
ROLL NO.- 204

2. Kingdom Plantae
Division Hepaticophyta
Class Hepaticopsida
Order Marchantiales
Family Marchantiaceae
Genus Marchantia
Species 65
Marchantia polymorpha, Marchantia berteroana,
Marchantia palmata, Marchantia nepalensis, etc….

3.  Genus has about 65 species.
 Grows best in cool, moist and shady places.
 Marchantia polymorpha grows as a pioneer in
burnt forest soil.
 11 species occur in India mainly in western Himalayas
 M.polymorpha occurs at high altitudes in Himalayas on moist
river banks and rocks.
 M.palmate occurs in Kashmir, Kumaon, South India, Bengal and
Assam.
 M.simlana occurs in Himachal Pradesh.
 M.nepalensis in Punjab and in Garhwal & Kumaon hills.

4. MORPHOLOGY
Plant body is prostrate, dorsiventral and
dichotomously branched…
GAMETOPHYTE
MARCHANTIA

5.  A shallow groove marked by the presence
of a distinct midrib in each branch.
 Many polygonal areas which demarcate the
outline of underlying air chambers.
 Each polygonal area has a pore in its
center called air pore.
 Gemma cups are present along the midrib.
 Each branch has a growing point situated
at the apex in a groove called apical notch.
DORSAL SURFACE
UPPER DORSAL SURFACE
DORSAL SURFACE

6. V
E
N
T
R
A
L
S
U
R
F
A
C
E
Bears
RHIZOIDS
and SCALES
along midrib…
LOWER VENTRAL SURFACE

7. RHIZOIDS
A. Unicellular and colorless
B. Two types -----------------------------
C. Smoothwalled- Inner walls are smoothand are
living cells.
D. Tuberculate- Inner walls showpeg like
ingrowths called tubercles and forms capillary
conducting system
E. Function– Anchorage and absorption of water and
minerals along with retaining moisture..

8. SCALES
A. Multicellular(one cell in thickness) and violet colored due to
presence of anthocyanin pigments.
B. Arranged in 2 rows on either side of mid-rib.
C. Two types--------------------------
D. Appendiculate– these have an apical sub-rotundappendage
and borne in the inner row of scales.
E. Ligulate– these are small, without appendage and present in
outer and middle rowof scales.
F. Function—Protection of growing point and retention of water
by capillary action…

9. Peg –
like
growths

10. INTERNAL
STRUCTURE

11.  On the dorsal and ventral surface of the thallus outermost single layered epidermis
is present.
 The upper epidermis consists of air pores which is barrel shaped and each pore has
4-8 superimposed tiers of cells where each tier consist of a ring of 4-5 cells.
 The pores have comparatively wide pore passage in the middle than on margins.
 These are analogous to stomata but they cannot control the pore size like stomata.
 The air chambers are present below upper epidermis.
 The air chambers are separated by partition walls.
 In air chamber there are photosynthetic filaments which are made up of cells which
are rich in chloroplast where food is synthesized. It is synthesizing zone.
 Below synthesizing zone, there is a region of compactly arranged parenchymatous
cells, which are thin, walled that store food. It is storage zone.
 Cells devoid of chloroplast and no intercellular spaces in between.
 Cells contain starch and protein granules. Mucilage and oil containing cells are also
present.
 Lower epidermis consists of number of rhizoids and scales.

14. ASEXUAL
REPRODUCTION:
1. Fragmentation
2. Adventitious Branches
3. By Gemmae

15. Fragmentation: Occurs by death and decay of posterior portion of
thallus.
Adventitious branches: Develop on any part of thallus, separate
and grow into new plant.
A-C:
FRAGMENTATIO
N
D-
ADVENTITIO
US
BRANCHES

16.  Gemma cups(2mmX3mm) are cupules
present on dorsal surface along midrib
region.
 Margins are hyaline, lobed, spiny or entire.
 From floor of gemma cup many small,
stalked, discoid & biconvex gemma arise.
 Gemma is constricted in middle and 2
notches possess a row of apical cells.
 Gemma contains chloroplast containing
cells and rhizoidal cells. Some mucilage
hairs also arise from Gemma cup’s floor
which imbibe water and help in dispersal
of gemmae.
 Gemmae on coming in contact with
ground start germinating immediately.
G
E
M
M
A
E
E
G M M A E
AIR CHAMBER
MUCILAGE HAIR
RHIZOID
THALLUS
RHIZOIDAL
INITIAL
CHLOROPLASTS

17. THALLUS GEMMA CUP

18. Marchantia is dioecious.
Male reproductive organ is antheridia and the female reproductive organ is
archegonia.
They are born on the mature gametophyte and are erect and modified
stalks known as antheridiophore and archegoniophore, respectively.
Antherozoids are produced in the antheridium. They are biflagellate and
produced from the androcytes.
The archegonium is a flask-shaped structure. It consists of several neck
canal cells, a ventral canal cell and an egg.
Male and female sex organs develop on different thalli.

19. a. Antheridiophore is differentiated into Stalk and
Disc.
b. Disc is 8-lobed, each representing a single
branch of thallus.
c. Disc is thick in middle and thin towards
periphery.
d. It resembles thallus and divided into air
chambers alternating with antheridial chambers.
e. Antheridia are borne inside antheridial chambers.
f. They are arranged in 8-radiating rows on dorsal
(upper) surface of disc, reach row representing a
single branch of thallus.
Antheridiophore

20. Antheridial Disc
ANTHERIDIOPHORE

21. Antheridia
 The air chambers on the upper surface are
alternated with numerous flask-shaped cavities,
called the Antheridial Chambers.
 The antheridial chambers open externally by a
pore, called Ostiole.
 Each antheridial chamber contains a single
Antheridium.
 The mature antheridium is a globular structure,
attached to the floor of the antheridial chamber
by a multicellular stalk.
 The antheridium has a single layered sterile
jacket, enclosing a mass of androcytes, which
eventually metamorphose into antherozoids
(minute, rod-like biflagellate male gametes).

22.  Also called Carpocephallum.
 It is differentiated into Stalk and Disc.
 Stalk is short and elongates after
fertilization.
 Stalk is short and elongates after
fertilization.
 Disc is 8-lobed directed away from
center.
 Archegonia develops on upper surface of
disc in acropetal (youngest archegonium
is near growing point of lobe and oldest
in the center of disc) succession in 8-
rows.
 Each row represent single lobe of thallus
and bears 12-18 archegonia.
 After fertilization, stalk elongates, central
portion of disc bulges out pushing archegonia
at periphery.
 It results in complete hanging (downward) of
archegonia.
 It shifts youngest archegonia to reach near
stalk and oldest and fertilized towards
periphery.
 Intercalary growth occurs between fertile lobes
which results in formation of radially elongated
green outgrowths called RAYS.
Archegoniophore

23. Archegoniophore

24.  Internal structure of disc shows
photosynthetic zone consists of air
chambers.
 The archegonia are arranged in 8-radiating
rows on lower surface of disc.
 Archegonia are inverted and hand
downward from tissue of disc.
 Each archegonia has an extra sheath called
PERIGYNIUM.
 Each group of archegonia are enclosed in
2-lipped involucres called
PERICHAETIUM.
 Mature archegonium is flask shaped
consists of stalk, venter and long neck.
 In mature archegonium, neck canal cells
and venter canal cells disintegrate and
become mucilaginous which absorbs water
and put pressure so as to get separated.
ARCHEGONIA
COVER CELLS
VENTER
CAVITY

25. 1. Occurs in presence of water.
2. Male and female thalli of
Marchantia grow in close
compact masses.
3. The antherozoids
(biflagellate)swim in cavity of disc
of antheridiophores.
4. The antherozoids fall on disc of
archegoniophore and flows
down to its neck and fuses with
egg.
5. Haploid nucleus of antherozoids
fuses with haploid nucleus of egg

26.  The zygote undergoes number of cell division during development and the
structure of zygote at that stage is called sporophyte.
 Each sporophyte is divided into FOOT, SETA and CAPSULE
 The basal portion of the sporophyte is called foot and middle elongated portion is
called seta.
 Round globular terminal part is called capsule which consists of thread like elaters
and number of unicellular spores formed by meiotic division in spore mother cells
within capsule.
 The capsule is surrounded by a layer called jacket.
 The whole sporophyte is surrounded by layer of cell called calyptra. Elaters help in
spore discharge when jacket or capsule is ruptured.
 The sporophyte is parasitic because it depends up on female gametophyte.
 Half of the spores germinate produce male gametophyte and half germinate to
produce female gametophyte.
SPOROPHYTE::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:::::::::::::::::::::::::

27. CAPSULE

28. I. Single layered capsule wall splits
into a no. of longitudinal valves
which extend from apex towards
the middle of capsule.
II. The valves are rolled back due to
annular thickenings in jacket
cells.
III.Jerky movement of elaters due to
their hygroscopic nature leads to
loosening up of spore mass and
scattering of spores in air.
Old Archegoniophores with attached
sporophytes
Dehiscence of sporophyte..

29. 1. Spores are viable for about a year.
2. Under favorable conditions they
absorb moisture from substratum and
increase in size.
3. Chloroplasts reappear at this stage.
4. Spore undergoes repeated divisions to
form 6-8 celled filamentous structure
with a rhizoid at one end.
5. The apical cell cuts off derivatives on
lateral sides and finally give rise to
gametophyte.
Germination of Spores

30. 1) Marchantia show alternation of generation, i.e. the
haploid sexual and diploid asexual phase alternates.
2) The life cycle of Marchantia is haplodiplontic.
3) Both the haploid and diploid phases are represented
by multicellular structures.
4) The main free-living plant body is the gametophyte
(haploid).
5) The short-lived sporophyte (diploid) stage is
dependent on the gametophyte for anchorage and
nourishment.
6) The male and female gametophyte gives rise to
antherozoids and an egg respectively, which fuse to
form the diploid zygote.
7) The zygote divides by mitotic division to form a
multicellular sporophyte.
8) The spore mother cells divide by meiosis to form the
haploid spore, which germinates to form the haploid
gametophyte.
LIFE
CYCLE OF
MARCHA-
NTIA..

31. BIBLIOGRAPHY
1. https://www.merospark.com/c
ontent/477/marchantia/
2. https://www.brainkart.com/art
icle/Marchantia---
Bryophytes_32874/
3. https://plantscience247.blogsp
ot.com/2020/07/marchantia-
classification-structure-
of.html
4. https://en.wikipedia.org/wiki/
Marchantia
5. https://www.britannica.com/pl
ant/Marchantia