Rhodophyta

by priyanka khare

1. TITLE :- RHODOPHYTA
NAME OF STUDENT :- PRIYANKA KHARE
COLLEGE NAME :- K.J.SOMAIYA COLLEGE OF SCI. & COM.
CLASS :- M. Sc. Part 1
FOR THE PAPER :- 1
FOR THE YEAR :- 2013-2014

2. RHODOPHYTA
 Commonly called as Red algae
Majority of the red algae are marine.
 Pigments :- r- phycocyanin , r- phycoerythrin , Chlorophylls , Carotenes &
Xanthophylls
 Reserved food material :- Floridean starch .
 Total absence of flagellated ( vegetative as well as reproductive ) bodies.
Classification as followed By G. M. Smith in 1933

3. RHODOPHYTA
RHODOPHYCEAE
Division
Class
Sub-class
Order
Order :-
Bangiodeae Florideae
Bangioles
Nemalionales Gelidiales Cryptonemiales Gigartinales Rhodymeniales
Ceramiales

4. Sub Class :- Bangioideae
Order :- Bangiales
E.g. :- Porphyra sps.
Porphyra perforata
 Thallus is a smooth to greatly convoluted blade
that is attached to the substratum by a disciform

or cushion like holdfast.
 Asexual reproduction by monospores.
 Sexual reproduction by directly division of
vegetative cells.
 Cells contain one or two chromatophores.
 It have a large centrally located pyrenoid .
Growing highly intertidal zone that’s why deep
olive brown in colour.

5. Sub Class :- Florideae
The forms are always multicellular.
 Plant body is filamentous . Filaments may aggregate
to form a psedoparenchymatous or flat thallus.
 Presence of pit connections in between the adjacent
cells.
 Auxiliary bud formation take place.
 Sexual reproduction is very complex.
 Male :- Spermatangium
Female :- Carpogonium
Plants are mostly marine.

6. Order 1 :- Nemalionales
Batrachospermum
E.g. :- Batrachospermum
 The body is bluish or violet green , multicellular ,
branched , soft , smooth.
 The main axis is differentiated into nodes &
internodes . From its node develop two types of
branches i.e. branches of unlimited growth &
branches of limited growth.
 Sexually reproduction oogamous type.
 Asexual reproduction by monospores.

7. Order 2 :- Gelidiales
Gelidium spp.
E.g. :- Gelidium
 It is famous for providing the best source of agar – agar
in the world.
 Thalli have a single apical cell at each branch apex.
 Carpogonial filament is unicellular & this single cell
constitutes the carpogonium .
 Tetrasporangia are usually crucinate.

8. Order 3 :- Cryptonemiales
E.g. :- Dudresnaya crassa
 An auxillary cell borne in special filament of the
gametophyte.
The thallus is monoaxial & with derivatives from
the single apical cell.
Each cutting off four lateral cells that are initials of
branched lateral filaments whose cells contain
chromatophores.
The gametophytes are heterothallic. Spermatangia
& Carpogonial filaments are borne in nemathecia
( sori ) i.e. conceptacles.
Dudresnaya crassa

9. Order 4 :- Gigartinales
E.g. :- Gigartina
 The thallus has more or less disciform holdfast
bearing one or more erect shoots.
 The gametophytes are heterothallic.
 A procarp consist of supporting cell bearing a
three celled Carpogonial filament.
The carposporophyte thus formed is freely
branched and with many short lateral branchlets
in which each cell develops into
carposporangium.
Gigartina

10. Order 5 :- Rhodymeniales
E.g. :- Gastroclonium coulteri
 Plant show multiaxial construction.
 Thallus is generally cylindrical, flattened or
hollow & contains apical or marginal
meristem.
 Plants are diplobiotic with a definite procarp.
 An auxillary cell is a special cell of the procarp
& differentiated before fertilization.
 Tetraspores are either tetrahedral or curciate.
Gastroclonium coulteri

11. Order 6 :- Ceramiales
Polysiphonia
E.g. :- Polysiphonia
 Thallus is uniaxial. The plant body is filamentous ,
psedoparenchymatous , reticulate & polysiphonous.
 The carpogonial branch is 4-celled .
 An auxillary cell is produced after fertilization . Carpospores
develop to form teterasporophytes .
 Haploid teraspores from gametophytes.
 Two types of branches , normal & trichoblasts.
 The cystocarp has a covering called as pericarp.

12. Reference Book :-

Algae by O. P. Sharma.

Cryptogamic Botany by G. M. Smith.