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
Commonly called as Red algae
Majority of the red algae are marine.
Pigments :- r- phycocyanin , r- phycoerythrin , Chlorophylls , Carotenes &
Reserved food material :- Floridean starch .
Total absence of flagellated ( vegetative as well as reproductive ) bodies.
Classification as followed By G. M. Smith in 1933
Nemalionales Gelidiales Cryptonemiales Gigartinales Rhodymeniales
Sub Class :- Bangioideae
Order :- Bangiales
E.g. :- Porphyra sps.
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
Cells contain one or two chromatophores.
It have a large centrally located pyrenoid .
Growing highly intertidal zone that’s why deep
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
Auxiliary bud formation take place.
Sexual reproduction is very complex.
Male :- Spermatangium
Female :- Carpogonium
Plants are mostly marine.
Order 1 :- Nemalionales
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.
Order 2 :- Gelidiales
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.
Order 3 :- Cryptonemiales
E.g. :- Dudresnaya crassa
An auxillary cell borne in special filament of the
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
The gametophytes are heterothallic. Spermatangia
& Carpogonial filaments are borne in nemathecia
( sori ) i.e. conceptacles.
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
Order 5 :- Rhodymeniales
E.g. :- Gastroclonium coulteri
Plant show multiaxial construction.
Thallus is generally cylindrical, flattened or
hollow & contains apical or marginal
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
Order 6 :- Ceramiales
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.
Reference Book :-
Algae by O. P. Sharma.
Cryptogamic Botany by G. M. Smith.