SlideShare ist ein Scribd-Unternehmen logo
1 von 40
Downloaden Sie, um offline zu lesen
ALGAE
GENERAL CHARACTERS, HABITAT, THALLUS
ORGANIZATION, REPRODUCTION,
ALGAE
Algae are small autotrophic plants that fail to show any cellular
differentiation. In simple we can call it chlorophyllous thallophytes.
ALGAE IN LATIN MEANS SEA WEEDS
The Algae word first used by Carolus Linnaeus 1753
(For a group of Bryophytes)
The actual delimitation
of a group plants from their macroscopical features
naming as Algae was done by Antoine Laurent De
Jussieu 1789
arvind wasnik
arvind wasnik
The branch of botany under which we study about Algae is known as
ALGOLOGY/PHYCOLOGY
The father of Algology is Felix Eugen Fritsch
The father of Modern Algology is William Henry Harvey
The Indian father of Algology is M.O.P. Iyengar
The book wrote by F.E. Fritsch was “The Structure and Reproduction of Algae”
Vol. I & II 1935
The two main phycologist of india work on algae are:
R. N. Singh- N2 fixing with the help of Blue Green Algae
P. K. Dey- Pioneer of N2 fixation
GENERAL CHARACTERS
Algae are simple, thalloid, autotrophic, non vascular having unicell sex
organs (exception multicellular sex organ in Chara) and no embryo formation (embryo 1st
forms in
Bryophyta)
In algae embryo did not formed because of zygotic meiosis. Due to zygotic meiosis haploid nuclei
are formed which further grow in to the new plants. Algae generally are Haploid in nature and for
very little duration diploid stage comes in the form of zygote. (If mitosis occurs in zygote results in
the formation of Embryo)
Unicellular Prokaryotes Monera
Ex: BGA
ALGAE Unicellular Eukaryotes Protista
Ex: Euglena
Multicellular Eukaryotes Plantae
Ex: Spirogyra
arvind wasnik
Algae differ from Bacteria in being eukaryotic in nature (except BGA)
Algae differ from Fungi in being autotrophic in nature
Algae differ from Bryophytes in not having a jacket of sterile cells
around their reproductive structures (except Chara, Bryophytes has
multicelled sex organ covered by sterile cell jacket while Algae has single cell sex organ
and are exposed)
BGA differ from bacteria in having oxygenic photosynthesis, it takes
water as electron donor and release O2 while Bacteria take electron
from hydrogen sulphide
In Algae oxygenic photosynthesis occurs due to Chl. a
arvind wasnik
GENERAL CHARACTERS
I. Habit: Algae are
Unicellular = Single
Multicellular = Colony/Filamentous
arvind wasnik
GENERAL CHARACTERS
II. Habitat: Algae may be
1. Aquatic Algae
2. Terrestrial Algae
3. Aerial Algae
4. Algae of Unusual Habitats
arvind wasnik
GENERAL CHARACTERS
1. Aquatic Algae may be
Fresh Water
OR
Marine
A. Fresh Water Still Water ( EX. Chara, Oedogonium, Zygnima)
Running Water ( Has Holdfast for attachment, EX.
Vaucheria, Ulothrix, Cosmopogan)
B. Marine Algae = Members of Phaeophyceae and Rhodophyceae like
Ectocarpus, Polysiphonia, Sargassum, Ulva.
arvind wasnik
GENERAL CHARACTERS
Terminologies used for Aquatic Algae:
Habit Habitat Example
1. Benthophytes Algae remains attached to any
substratum ( growing on mud and
other bottom )
The Benthic Algae may be
Epipelic Epipsammic
Grows on Sediments Located on Sand
Ex. Oedogonium
Annual Perennial
Ex. Porphyra Ex. Sargassum
Fresh Water are
Chara, Nitella
Marine are members
of Phaeophyceae and
Rhodophyceae
2. Epactiphytes Growing along shores of lakes or
ponds.
Ex. Spirogyra,
Chaetophora.
3. Neustonic They grow on water surface Ex. Hydrodictyon
arvind wasnik
Habit Habitat Example
4.Thermophytes Growing in thermal water can tolerate
very high temperature
Based on temp.
Hypothermae ( Below 18 ‘C)
Hliarothermae (18- 30 ‘C)
Euthermae (30 -50 ‘C)
Aerothermae (50 -70 ‘C)
Hyperthermae ( Above 70’C)
Majority of thermal
algae belongs to
Myxophyceae group
Ex. Synechococus elongatus,
Mastigocladus laminosus
5. Planktophytes Floating Algae.
Are of two types:
1.Euplanktophytes: True floating Algae
ex. Volvox, Hydrodictyon
2.Tychoplanktophytes: Becomes
floating accidentally ex. Oedogonium,
Nostoc
Ex. Spirulina, Volvox,
Euglena, Chlorella,
Chlamydomonas etc
arvind wasnik
ALGAL BLOOM
Abundant growth of planktonic algae begin to impart colour to the water, such
phenomenon is called Water Bloom as caused due to algae so called as Algal Water
Bloom. Formation of blooms depends on temp. increase and nutrient availability.
Water Bloom may be
Temporary/Permanent
Mixed/Pure
1. Temporary & Mixed type are produced by Chlamydomonas, Scendesmus,
Chlorella, Ankistrodesmus, Pediastrum etc.
2. Temporary & Pure contains only one species Volvox globator or Chlamydomonas
sp.
3. Permanent & Mixed are made up of Anabaena, Anabaenopsis, Microcystis etc.
4. Permanent & Pure
a. Trichodesmium sp forms a permanent red water bloom in red sea.
b. Microcystis aeruginosa forms permanent blue green water bloom in temple
ponds.
arvind wasnik
Habit Habitat Example
6. Halophytes Growing in saline habitat
In salt lakes ex. Chlamydomonas
ehrenberghii
In salt springs ex. Enteromorpha sp.
Dunaliella etc
7. Epiphytes Growing attached on other plants or
algae.
Epiphytic algae on submerged
hydrophytes known as Periphyton
Choleocheate in
association with Chara
& Nitella
Cladophora on leaves
of Vallisneria &
Nelumbo
Oedogonium on
Hydrilla
8. Epizoophytes Grows on aquatic organisms Cladophora crispata on
Snail Shell
Characium on
Mosquito Larva
Protoderma on Turtle
Shell
arvind wasnik
GENERAL CHARACTERS
2. TERRESTRIAL ALGAE
Algae that grows on or in soil called as Edaphophytes
a. Sapophytes- Algae grows on the soil surface ex.
Vaucheria
b.Cryptophytes- Algae grows in the soil, fix nitrogen for
the soil fertility ex. Nostoc, Anabeana
arvind wasnik
GENERAL CHARACTERS
3. AERIAL ALGAE
Habitat is aerial and are called as Aerophytes
Habit Habitat Example
1. Epiphyllophytes Grows on the leaves of terrestrial plants Trentopholia sp on the
leaves of Butea
monosperma
2. Epiphloephytes
or
Corticolous
Growing on the Mosses, Liverworts and on the
Barks
Ex. Pleurococus,
Microcolous.
3. Epizoophytes They grow on the body of terrestrial animals Ex. Cyanoderma on the
hairs of Sloth Bear
4. Lithophytes Growing attached to stones and rocky surface
a.Epilithic- On rock surface ex. Calothrix
b.Endolithic- Inside the rock or inside the
skeleton of corals ex. Dalmatella
c.Chasmolithic- Grows in rock fissures ex.
Gleocapsa
arvind wasnik
GENERAL CHARACTERS
4. Algae of Unusual Habitat
A. Cryophytes: Algae grow on Ice or Snow
Only on snow- Raphidonema
Only on ice- Ancyclonema
On both ice & snow- Trachiscia
Not true cryophytes-Phormidium
In Europe some mountain become green colour due to Raphidonema
Yellowishgreen due to Chlamydomonas yellowstonensis
Red colour due to Chlamydomonas nivalis (Arctic & Alpine Region)
Brown colour due to Ancyclonema nordenskioldii
Yellow colour due to Protoderma
Green colour due to Scotiella
arvind wasnik
GENERAL CHARACTERS
B. Symbionts
Some Algae live in association with certain Plants and Animals
1. Endophytic Algae: With Plants
Nostoc in Anthoceros
Anabeana cycadeae in the corolloid root of Cycas
BGA Cyanailae in Protozoa
2. Endozoic Algae: With Animals
Zoochlorella in Hydra viridis
Trochisia sp. In Rana agilis
Oedogonium undulatum in Insect Larva
Oscillospira sp. In Guinea Pig
arvind wasnik
GENERAL CHARACTERS
C. Parasitic Algae
Some BGA like Simonosiella sp. are found as
parasite in the Human Intestine
Cephaleuros virescens grows on the leaf of Thea
sinensis (Tea Plant) and cause the disease
known as Red Rust
arvind wasnik
GENERAL CHARACTERS
III. THALLUS ORGANIZATION
Vegetative body of Algae is called as thallus
It is not differentiated in to Root, Stem and Leaf, so algae are simple plants
arvind wasnik
GENERAL CHARACTERS
A. Unicellular- All vital function of life performed by a single cell, these are of
1. Flagellated/Motile
2. Amoeboid/Rhizopodial
3. Non-Motile/Coccoidal
1. Flagellated/Motile Form: Have flagella
One Flagella ex. Trachelomonas, Chromulina
Two Flagella- When both flagella are equal in size is called Isokont
ex. Chlamydomonas, Haematococcus
When both flagella are unequal in size called Hetrokont ex. Gonyostomum
arvind wasnik
GENERAL CHARACTERS
2. Amoeboid/Rhizopodial Form
Having protoplasmic projection called pseudopodia
ex. Chrysamoeba
3. Non Motile/Coccoidal Form
Lack cell wall and no locomotary organ ex, Diatoms, Chlorella
arvind wasnik
GENERAL CHARACTERS
B. MULTICELLULAR THALLUS: Multicelled Thallus
1. Colony: It is formed by the aggregation of individual cells
a. Coenobium- A colony with definite numbers of cells and having a constant
shape and size
Non Motile :
Aggregations of non-motile cells in the form of a colony (non-motile) are
common only in Chlorophyceae. Here the cells are, more or less, fused
together (e.g., Hydrodictyon) or connected by mucilaginous threads (e.g.,
Dictyosphaerium) and the colony may be of various shapes. It may be plate
like e.g.. Scenedesmus or net-like as in Hydrodictyon.
arvind wasnik
Motile
Motile flagellated cells aggregate together to form motile
colonies. Colonies vary in shape and size and in the number of cells.
The colonies are either “plate-like” (e.g., Gonium) or spherical
(e.g., Volvox).
arvind wasnik
arvind wasnik
Pamelloid
In a large number of genera this habit is a permanent one e.g., Tetraspora
(Chlorophyceae), Phaeocystis (Chrysophyceae) or is a temporary phase, in the life-
cycle e.g., Chlamydomonas (Chlorophyceae) Chromulina, (Chrysophyceae). The
habit is named after the genus Palmella (Palmeflaceae, Chlorophyceae)
Here the individual lion-flagellated cells have mucilaginous sheaths around
them and are enveloped in a common gelatinous matrix of indefinite shape which
may be microscopic or macroscopic in size.
arvind wasnik
Dendroid
A variation of the palmelloid condition is seen in
dendroid colonies. Here the mucilage is produced locally, generally at the
base of the cell.
Dendroid forms are seen e.g. Prasinocladus (Chlorophyceae),
Mischococcus (Xanthophyccae) and in Chrysophyceae and Euglenineae
2. Filamentous Forms:
 the division of the single cell into many daughter cells with septa between the divided
cells a filamentous type of construction would be formed.
(i) Un-branched Filaments:
 Simple un-branched filaments are found in many forms. They are either
free-living e.g., Spirogyra or attached, at least initially e.g., Oedogonium, or
aggregated in colonies e.g., Nostoc
arvind wasnik
(ii) Branched Filaments:
 (i) Simple
 (ii) Heterotrichous
 (iii) Pseudoparenchymatous
(i) Simple
A simple branched filament with dichotomous branching pattern and a basal
attaching cell, holdfast or hapteron is common with many types e.g.,
Cladophora. A peculiar form of branching, known as ‘false’-branching is
observed in Cyanophyceae e.g., Scytonema
arvind wasnik
arvind wasnik
(ii) Heterotrichous
This most highly evolved type of plant-body, showing a good amount
of division of labour.
The plant-body consists of two distinct parts:
(1) A basal or prostrate creeping system, and
(2) An erect or upright system.
The prostrate system is attached to some substratum, grows apically and
gives rise to numerous photosynthetic and rhizoidal filaments. Rhizoidal filaments
sometimes penetrate the substratum . The erect system develops from the prostrate
system and is composed of one or more and usually branched photosynthetic filaments.
In Stigeoclonium and Trentepohlia these two systems are equally
developed and easily distinguished.
Whereas in Coleochaete (Chlorophyceae) and Ascocyclus (Phaeophyceae) the
prostrate system is highly elaborated and the erect system is reduced. This
gives the body a discoid type of appearance. On the other hand, in many
species of Ectocarpus, the prostrate system is reduced, and the erect system
is well developed. This gives the body a crust or cushion type of appearance.
In many cases the reduction of one system has gone to the limit of practical
elimination. Thus in an endophytic species, Endoderia and in Chaetopeltis
(Chlorophyceae) only the prostrate system is developed. Complete absence
of prostrate system is noticed in Microthamnion.
arvind wasnik
(iii) Pseudoparenchymatous forms:
As indicated by the term ‘pseudo’ = false, the plant body gives the
appearance of parenchymatous construction. The pseudoparenchymatous
structure is a secondary development, close association of cells is a result of
interweaving of filaments. Intercellular connections may be densely packed
and firmly coherent (e.g., Dumontia, Rhodophyceae) or, the association may
be loose and can easily be separated by pressure (e.g., Castanea,
Phaeophyceae).
Two types are: (1) uniaxial construction = a single colourless central axial
filament e.g., Batrachospermum
(2) multi-axial = many filaments e.g., Polysiphonia
arvind wasnik
5. Siphonaceous Forms:
 In a number of algae, belonging to Siphonales e.g., in Vaucheria, Botrydium,
the growth of the plant body takes place without the usual cross-wall
formation except during formation of reproductive organs. Thus a ‘tube’-
like multinucleate structure, or a coenocyte, is produced.
arvind wasnik
6. Parenchymatous Forms:
Parenchymatous thallus organization also is a modification of the
filamentous habit, with cell division in more than one plane. The
parenchymatous thalli may be ‘leaf-like’ or foliose, tubular or highly
developed structure.
Foliose or Tubular thalli are formed by the division of the cells two or
three planes. Common examples of foliose structures in Viva
(Chlorophyceae), Porphyra (Rhodophyceae). The example of tubular
structure is Enteromorpha (Chlorophyceae).
arvind wasnik
Reproduction Found in Algae
There are three common methods of reproduction found in algae – (i)
vegetative, (ii) asexual, and (iii) sexual.
 1. Vegetative reproduction:
This may be of several types.
(i) By cell division:
The mother cells divide and the daughter cells are produced, which become
new plants. This is exclusive type of reproduction in Pleurococcus, some
desmids, diatoms, Euglena, etc.
(ii) Fragmentation:
The plant body breaks into several parts or fragments and each such
fragment develops into an individual. This type of vegetative reproduction is
commonly met within filamentous forms, e.g., Ulothrix, Spirogyra, etc. The
fragmentation of colonies also takes place in several blue green algae, e.g.,
Aphanocapsa, Aphanothece, Nostoc, etc.
arvind wasnik
arvind wasnik
(iii) Hormogone formation:
When the trichomes break in small pieces of two or more cells, such pieces are called
‘hormogones’. Each hormogone develops into a new plant, e.g., Oscillatoria, Nostoc, etc.
(iv) Hormospores or hormocysts:
They are thick-walled hormogones, and produced in somewhat drier conditions.
(v) By adventitious thalli:
Certain special structures of thalli are formed which help in vegetative reproduction. The
well known propagula of Bryopsis, Sphacelaria and Nereocystis are good examples.
(vi) By primary secondary protonema:
Such thread-like vegetative bodies develop in the case of Chara, which help in
reproduction.
(vii) Tubers:
Usually these bodies are rounded and filled up with abundance of starch. Each body may
give rise to a new plant, e.g., Chara.
(viii) Starch or amylum stars:
Such special star-shaped, starch filled bodies give rise to new plants frequently reported
from Chara.
arvind wasnik
(ix) Bulbils:
Small bud-like structures. Usually develop on the rhizoids of Chara are called bulbils. Each
such bulbil may develop into a new plant.
(x) Akinetes:
In most of the Chlorophyceae members, the Akinetes are developed. Usually the protoplast
of each cell converts in a single akinete. Sometimes they are formed in chains. Each
akinete may develop into a new plant, e.g., Oedogonium, Ulothrix, etc.
2. Asexual reproduction:
Usually the protoplast of a cell divides into several protoplasts and thereafter they escape
from the mother and develop into new plants.
(i) By zoospores:
The zoospores are formed from certain older cells of the filaments. The cytoplasm divides
to form zoospores which are escaped from the mother cell. They are always formed in
favourable conditions. The zoospores are always motile. They may be (i) biflagellate, (ii)
tetraflagellate, (iii) stephanokontean type of zoospores, e.g., Oedogoniales and (iv)
compound zoospores, e.g., Vaucheriaceae
arvind wasnik
(ii) By aplanospores:
When motile phase of zoospores is eliminated, the bodies are called
aplanospores. The aplanospores develop in unfavourable conditions. Each such
spore is surrounded by a wall.
(iii) By hypnospores:
Actually they are very thick-walled aplanospores and develop only in adverse
conditions, e.g., Pediastrum, Vaucheria.
(iv) Palmella stage:
Here the successive generations of divided cells are gelatinized and a thick
mucilaginous envelope develops, e.g., Chlamydomonas, Ulothrix, etc.
(v) Autospores:
They are just like aplanospores except that they are smaller in size. They
resemble in shape to mother cell except in size. Each autospore gives rise to a
new plant. Such autospores are reported from many Chlorococcales.
(vi) Endospores:
In many blue green algae and Bacillariophyceae, the endospores are formed
within the cells. On the approach of favourable conditions, each endospore
develops in a new individual.
(vii) Exospores:
arvind wasnik
(viii) Carpospores:
They are found in the carposporophytes of red algae (Rhodophyceae). Each such spore
develops in a new individual.
(ix) Tetra spores:
(x) Monospores:
These spores develop within monosporangia. Each spore gives rise to a new plant, e.g.,
many members of Rhodophyceae (Bangia, Porphyra, Porphyridium, etc).
(xi) Paraspores:
Such spores are reported from many members of Rhodophyceae. Each spore develops into
a new plant.
(xii) Statospores:
They are found in Xanthophyceae and Bacillariophyceae where they act as perennating
bodies.
(xiii) Daughter colonies:
In many Volvocales and Chlorococcales, the daughter colonies are developed asexually,
e.g., Volvox, Hydrodictyon, Pediastrum, etc.
(xiv) Gongrosira stage of Vaucheria:
In the aseptate filaments of Vaucheria, the protoplast divides into several parts, several
hypnospores or cysts are produced and the whole filament looks like an algal form
‘Gongrosira’.
(xv) Microspores:
They are produced in many Bacillariophyceae.
arvind wasnik
arvind wasnik
It is greatly advanced method of reproduction and not known in Myxophyceae
(blue green algae). There are two main types, i.e., (i) isogamy and (ii)
heterogamy.
(i) Isogamy:
The fusion of similar motile gametes is found in many species. Usually the
gametes taking part in fusion come from two different individuals or filaments,
sometimes these gametes come from two different cells of the same filament.
Thousands of gametes come and aggregate in clumps. (See Fig. 3.8).
(ii) Heterogamy:
The fusion of dissimilar gametes is called heterogamy. There are variations of it.
(a) Anisogamy:
The motile gametes taking part in fusion may either differ in size (morphological
anisogamy) or physiological behaviour (physiological anisogamy).
(b) Oogamy:
In this case, the male antherozoid fuses with the female egg. This fusion may be
of primitive type as found in Cylindrocapsa, or advanced type as in Oedogonium,
Vaucheria, Chara, Polysiphonia, etc.
arvind wasnik
(iii) Aplanogamy or conjugation:
It implies the fusion of two non-flagellate amoeboid gametes (aplanogametes).
They are morphologically similar but physiologically dissimilar, e.g., order
Conjugales.
In fresh water algae, the sexual reproduction is best means of perennation because
it is followed by the formation of thick-walled zygote or oospore.
Parthenogenesis:
The female gametes convert into zygotes without fusion. The resultants are called
azygospores or parthenospores and the phenomenon ‘parthenogenesis’, e.g.,
Spirogyra, Oedogonium and many others.
Autogamy:
In this phenomenon, the fusion of the daughter protoplasts or of the divided nuclei
of a cell without liberation takes place. This process is known in many diatoms and
colour-less dinoflagellates.
arvind wasnik

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Pigmentation in-algae-ppt-
Pigmentation in-algae-ppt-Pigmentation in-algae-ppt-
Pigmentation in-algae-ppt-
 
Stelar evolution in Pteridophytes-BOTANY
Stelar evolution in Pteridophytes-BOTANYStelar evolution in Pteridophytes-BOTANY
Stelar evolution in Pteridophytes-BOTANY
 
General Characters of Phaeophyceae & Life Cycle of Sargassum SMG
General Characters of Phaeophyceae & Life Cycle of Sargassum   SMGGeneral Characters of Phaeophyceae & Life Cycle of Sargassum   SMG
General Characters of Phaeophyceae & Life Cycle of Sargassum SMG
 
Chlorophyceae green Algae
Chlorophyceae green AlgaeChlorophyceae green Algae
Chlorophyceae green Algae
 
Cyanophyta
CyanophytaCyanophyta
Cyanophyta
 
Sphagnum
SphagnumSphagnum
Sphagnum
 
Algae
AlgaeAlgae
Algae
 
Xanthophyceae
XanthophyceaeXanthophyceae
Xanthophyceae
 
Chlorophyta
ChlorophytaChlorophyta
Chlorophyta
 
Lichens ppt
Lichens pptLichens ppt
Lichens ppt
 
Economic and Ecological Importance of Bryophytes.pptx
Economic and Ecological Importance of Bryophytes.pptxEconomic and Ecological Importance of Bryophytes.pptx
Economic and Ecological Importance of Bryophytes.pptx
 
Rhodophyta
RhodophytaRhodophyta
Rhodophyta
 
Chara
CharaChara
Chara
 
Cycas
CycasCycas
Cycas
 
Classification of pteridophytes
Classification of pteridophytesClassification of pteridophytes
Classification of pteridophytes
 
Oedogonium
OedogoniumOedogonium
Oedogonium
 
Selaginella
SelaginellaSelaginella
Selaginella
 
Nostoc
NostocNostoc
Nostoc
 
Lichen powerpoint presentation
Lichen powerpoint  presentationLichen powerpoint  presentation
Lichen powerpoint presentation
 
Rhynia
RhyniaRhynia
Rhynia
 

Ähnlich wie ALGAE General Characters

Ähnlich wie ALGAE General Characters (20)

Algae (1).pdf
Algae (1).pdfAlgae (1).pdf
Algae (1).pdf
 
Algae introduction
Algae introductionAlgae introduction
Algae introduction
 
Algae
AlgaeAlgae
Algae
 
algae.pptx
algae.pptxalgae.pptx
algae.pptx
 
Classification of algae
Classification of algaeClassification of algae
Classification of algae
 
Algae classification
Algae classificationAlgae classification
Algae classification
 
ALGAE.pptx
ALGAE.pptxALGAE.pptx
ALGAE.pptx
 
Classification of Algae
Classification of AlgaeClassification of Algae
Classification of Algae
 
Tawqir Bashir (Lecture 11)_MB.pdf
Tawqir Bashir (Lecture 11)_MB.pdfTawqir Bashir (Lecture 11)_MB.pdf
Tawqir Bashir (Lecture 11)_MB.pdf
 
Phyccology
PhyccologyPhyccology
Phyccology
 
Final ppt. in biodiversity
Final ppt. in biodiversityFinal ppt. in biodiversity
Final ppt. in biodiversity
 
Chlorophyceae.pptx
Chlorophyceae.pptxChlorophyceae.pptx
Chlorophyceae.pptx
 
Algae.pdf
Algae.pdfAlgae.pdf
Algae.pdf
 
Algae.pdf
Algae.pdfAlgae.pdf
Algae.pdf
 
Algae.pdf
Algae.pdfAlgae.pdf
Algae.pdf
 
Algae.pdf
Algae.pdfAlgae.pdf
Algae.pdf
 
Phycology algae ... presentation
Phycology  algae ... presentationPhycology  algae ... presentation
Phycology algae ... presentation
 
l9_0.pptzhzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
l9_0.pptzhzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzl9_0.pptzhzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
l9_0.pptzhzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
 
Algae (DIVERSITY OF MICROBES)
Algae (DIVERSITY OF MICROBES)Algae (DIVERSITY OF MICROBES)
Algae (DIVERSITY OF MICROBES)
 
Intro to algae aaabbbcccdddjwnjdjdjjdjhhh
Intro to algae aaabbbcccdddjwnjdjdjjdjhhhIntro to algae aaabbbcccdddjwnjdjdjjdjhhh
Intro to algae aaabbbcccdddjwnjdjdjjdjhhh
 

Mehr von Praveen Koushley (20)

Research Methodology
Research MethodologyResearch Methodology
Research Methodology
 
Fossil gymnosperms
Fossil gymnospermsFossil gymnosperms
Fossil gymnosperms
 
Thus spake the buddha
Thus spake the buddhaThus spake the buddha
Thus spake the buddha
 
Demography
DemographyDemography
Demography
 
Ecological niche
Ecological nicheEcological niche
Ecological niche
 
Group theory and symmetry
Group theory and symmetryGroup theory and symmetry
Group theory and symmetry
 
Women impowerment
Women impowermentWomen impowerment
Women impowerment
 
The tempest a play by william shakspeare
The tempest a play by william shakspeareThe tempest a play by william shakspeare
The tempest a play by william shakspeare
 
Soil profile
Soil profileSoil profile
Soil profile
 
Microtomy
MicrotomyMicrotomy
Microtomy
 
Inside the earth
Inside the earthInside the earth
Inside the earth
 
Impact of human activities on soil
Impact of human activities on soilImpact of human activities on soil
Impact of human activities on soil
 
Geomorphology
GeomorphologyGeomorphology
Geomorphology
 
Emergency provisions in indian constitution
Emergency provisions in indian constitutionEmergency provisions in indian constitution
Emergency provisions in indian constitution
 
Basic features of indian constitution
Basic features of indian constitutionBasic features of indian constitution
Basic features of indian constitution
 
Introduction to ricardian theory
Introduction to ricardian theoryIntroduction to ricardian theory
Introduction to ricardian theory
 
Simple harmonic motion
Simple harmonic motionSimple harmonic motion
Simple harmonic motion
 
Computer Basics
Computer BasicsComputer Basics
Computer Basics
 
Crystal structure
Crystal structureCrystal structure
Crystal structure
 
OLEDs
OLEDsOLEDs
OLEDs
 

Kürzlich hochgeladen

Probiotics by Thangjam Leonath Singh of DM college
Probiotics by Thangjam Leonath Singh of DM collegeProbiotics by Thangjam Leonath Singh of DM college
Probiotics by Thangjam Leonath Singh of DM collegeThangjamLeonathSingh
 
Potato spindle tuber disease VIRIOID DISEASE
Potato spindle tuber disease  VIRIOID DISEASEPotato spindle tuber disease  VIRIOID DISEASE
Potato spindle tuber disease VIRIOID DISEASEKARTHIK REDDY C A
 
GNU Linux - Introduction and Administration
GNU Linux - Introduction and AdministrationGNU Linux - Introduction and Administration
GNU Linux - Introduction and AdministrationXavier de Pedro
 
BACTERIAL SECRETION SYSTEM by Dr. Chayanika Das
BACTERIAL SECRETION SYSTEM by Dr. Chayanika DasBACTERIAL SECRETION SYSTEM by Dr. Chayanika Das
BACTERIAL SECRETION SYSTEM by Dr. Chayanika DasChayanika Das
 
chapter 28 Reproductive System Power Point
chapter 28 Reproductive System Power Pointchapter 28 Reproductive System Power Point
chapter 28 Reproductive System Power Pointchelseakland
 
Timeless Cosmology: Towards a Geometric Origin of Cosmological Correlations
Timeless Cosmology: Towards a Geometric Origin of Cosmological CorrelationsTimeless Cosmology: Towards a Geometric Origin of Cosmological Correlations
Timeless Cosmology: Towards a Geometric Origin of Cosmological CorrelationsDanielBaumann11
 
Physical pharmacy unit 1 solubility of drugs.pptx
Physical pharmacy unit 1 solubility of drugs.pptxPhysical pharmacy unit 1 solubility of drugs.pptx
Physical pharmacy unit 1 solubility of drugs.pptxchetanvgh
 
General.physics 2-quarter 4-WEEK-EM WAVES
General.physics 2-quarter 4-WEEK-EM WAVESGeneral.physics 2-quarter 4-WEEK-EM WAVES
General.physics 2-quarter 4-WEEK-EM WAVESElaisaBassig
 
Total Legal: A “Joint” Journey into the Chemistry of Cannabinoids
Total Legal: A “Joint” Journey into the Chemistry of CannabinoidsTotal Legal: A “Joint” Journey into the Chemistry of Cannabinoids
Total Legal: A “Joint” Journey into the Chemistry of CannabinoidsMarkus Roggen
 
Introduction of Organ-On-A-Chip - Creative Biolabs
Introduction of Organ-On-A-Chip - Creative BiolabsIntroduction of Organ-On-A-Chip - Creative Biolabs
Introduction of Organ-On-A-Chip - Creative BiolabsCreative-Biolabs
 
Remote patient monitoring :Health care transformation
Remote patient monitoring :Health care transformationRemote patient monitoring :Health care transformation
Remote patient monitoring :Health care transformationfahad Alotaibiu
 
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENT
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENTMEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENT
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENTLits IT
 
FBI Profiling - Forensic Psychology.pptx
FBI Profiling - Forensic Psychology.pptxFBI Profiling - Forensic Psychology.pptx
FBI Profiling - Forensic Psychology.pptxPayal Shrivastava
 
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer Zahana
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer ZahanaEGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer Zahana
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer ZahanaDr.Mahmoud Abbas
 
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...Chayanika Das
 
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptx
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptxPharmaceutical warehouse audit using eAuditor Audits & Inspections .pptx
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptxeAuditor Audits & Inspections
 
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdf
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdfCDS Fundamentals of digital communication system UNIT 1 AND 2.pdf
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdfshubhangisonawane6
 
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...Speed Breeding in Vegetable Crops- innovative approach for present era of cro...
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...jana861314
 
Presentation about adversarial image attacks
Presentation about adversarial image attacksPresentation about adversarial image attacks
Presentation about adversarial image attacksKoshinKhodiyar
 
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTH
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTHULTRA STRUCTURE OF FUNGAL CELL AND GROWTH
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTHKARTHIK REDDY C A
 

Kürzlich hochgeladen (20)

Probiotics by Thangjam Leonath Singh of DM college
Probiotics by Thangjam Leonath Singh of DM collegeProbiotics by Thangjam Leonath Singh of DM college
Probiotics by Thangjam Leonath Singh of DM college
 
Potato spindle tuber disease VIRIOID DISEASE
Potato spindle tuber disease  VIRIOID DISEASEPotato spindle tuber disease  VIRIOID DISEASE
Potato spindle tuber disease VIRIOID DISEASE
 
GNU Linux - Introduction and Administration
GNU Linux - Introduction and AdministrationGNU Linux - Introduction and Administration
GNU Linux - Introduction and Administration
 
BACTERIAL SECRETION SYSTEM by Dr. Chayanika Das
BACTERIAL SECRETION SYSTEM by Dr. Chayanika DasBACTERIAL SECRETION SYSTEM by Dr. Chayanika Das
BACTERIAL SECRETION SYSTEM by Dr. Chayanika Das
 
chapter 28 Reproductive System Power Point
chapter 28 Reproductive System Power Pointchapter 28 Reproductive System Power Point
chapter 28 Reproductive System Power Point
 
Timeless Cosmology: Towards a Geometric Origin of Cosmological Correlations
Timeless Cosmology: Towards a Geometric Origin of Cosmological CorrelationsTimeless Cosmology: Towards a Geometric Origin of Cosmological Correlations
Timeless Cosmology: Towards a Geometric Origin of Cosmological Correlations
 
Physical pharmacy unit 1 solubility of drugs.pptx
Physical pharmacy unit 1 solubility of drugs.pptxPhysical pharmacy unit 1 solubility of drugs.pptx
Physical pharmacy unit 1 solubility of drugs.pptx
 
General.physics 2-quarter 4-WEEK-EM WAVES
General.physics 2-quarter 4-WEEK-EM WAVESGeneral.physics 2-quarter 4-WEEK-EM WAVES
General.physics 2-quarter 4-WEEK-EM WAVES
 
Total Legal: A “Joint” Journey into the Chemistry of Cannabinoids
Total Legal: A “Joint” Journey into the Chemistry of CannabinoidsTotal Legal: A “Joint” Journey into the Chemistry of Cannabinoids
Total Legal: A “Joint” Journey into the Chemistry of Cannabinoids
 
Introduction of Organ-On-A-Chip - Creative Biolabs
Introduction of Organ-On-A-Chip - Creative BiolabsIntroduction of Organ-On-A-Chip - Creative Biolabs
Introduction of Organ-On-A-Chip - Creative Biolabs
 
Remote patient monitoring :Health care transformation
Remote patient monitoring :Health care transformationRemote patient monitoring :Health care transformation
Remote patient monitoring :Health care transformation
 
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENT
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENTMEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENT
MEDICINE & ALIED SUBJECT PDF BOOK FOR MEDICAL STUDENT
 
FBI Profiling - Forensic Psychology.pptx
FBI Profiling - Forensic Psychology.pptxFBI Profiling - Forensic Psychology.pptx
FBI Profiling - Forensic Psychology.pptx
 
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer Zahana
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer ZahanaEGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer Zahana
EGYPTIAN IMPRINT IN SPAIN Lecture by Dr Abeer Zahana
 
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...
ESSENTIAL FEATURES REQUIRED FOR ESTABLISHING FOUR TYPES OF BIOSAFETY LABORATO...
 
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptx
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptxPharmaceutical warehouse audit using eAuditor Audits & Inspections .pptx
Pharmaceutical warehouse audit using eAuditor Audits & Inspections .pptx
 
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdf
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdfCDS Fundamentals of digital communication system UNIT 1 AND 2.pdf
CDS Fundamentals of digital communication system UNIT 1 AND 2.pdf
 
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...Speed Breeding in Vegetable Crops- innovative approach for present era of cro...
Speed Breeding in Vegetable Crops- innovative approach for present era of cro...
 
Presentation about adversarial image attacks
Presentation about adversarial image attacksPresentation about adversarial image attacks
Presentation about adversarial image attacks
 
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTH
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTHULTRA STRUCTURE OF FUNGAL CELL AND GROWTH
ULTRA STRUCTURE OF FUNGAL CELL AND GROWTH
 

ALGAE General Characters

  • 1. ALGAE GENERAL CHARACTERS, HABITAT, THALLUS ORGANIZATION, REPRODUCTION,
  • 2. ALGAE Algae are small autotrophic plants that fail to show any cellular differentiation. In simple we can call it chlorophyllous thallophytes. ALGAE IN LATIN MEANS SEA WEEDS The Algae word first used by Carolus Linnaeus 1753 (For a group of Bryophytes) The actual delimitation of a group plants from their macroscopical features naming as Algae was done by Antoine Laurent De Jussieu 1789 arvind wasnik
  • 3. arvind wasnik The branch of botany under which we study about Algae is known as ALGOLOGY/PHYCOLOGY The father of Algology is Felix Eugen Fritsch The father of Modern Algology is William Henry Harvey The Indian father of Algology is M.O.P. Iyengar The book wrote by F.E. Fritsch was “The Structure and Reproduction of Algae” Vol. I & II 1935 The two main phycologist of india work on algae are: R. N. Singh- N2 fixing with the help of Blue Green Algae P. K. Dey- Pioneer of N2 fixation
  • 4. GENERAL CHARACTERS Algae are simple, thalloid, autotrophic, non vascular having unicell sex organs (exception multicellular sex organ in Chara) and no embryo formation (embryo 1st forms in Bryophyta) In algae embryo did not formed because of zygotic meiosis. Due to zygotic meiosis haploid nuclei are formed which further grow in to the new plants. Algae generally are Haploid in nature and for very little duration diploid stage comes in the form of zygote. (If mitosis occurs in zygote results in the formation of Embryo) Unicellular Prokaryotes Monera Ex: BGA ALGAE Unicellular Eukaryotes Protista Ex: Euglena Multicellular Eukaryotes Plantae Ex: Spirogyra arvind wasnik
  • 5. Algae differ from Bacteria in being eukaryotic in nature (except BGA) Algae differ from Fungi in being autotrophic in nature Algae differ from Bryophytes in not having a jacket of sterile cells around their reproductive structures (except Chara, Bryophytes has multicelled sex organ covered by sterile cell jacket while Algae has single cell sex organ and are exposed) BGA differ from bacteria in having oxygenic photosynthesis, it takes water as electron donor and release O2 while Bacteria take electron from hydrogen sulphide In Algae oxygenic photosynthesis occurs due to Chl. a arvind wasnik
  • 6. GENERAL CHARACTERS I. Habit: Algae are Unicellular = Single Multicellular = Colony/Filamentous arvind wasnik
  • 7. GENERAL CHARACTERS II. Habitat: Algae may be 1. Aquatic Algae 2. Terrestrial Algae 3. Aerial Algae 4. Algae of Unusual Habitats arvind wasnik
  • 8. GENERAL CHARACTERS 1. Aquatic Algae may be Fresh Water OR Marine A. Fresh Water Still Water ( EX. Chara, Oedogonium, Zygnima) Running Water ( Has Holdfast for attachment, EX. Vaucheria, Ulothrix, Cosmopogan) B. Marine Algae = Members of Phaeophyceae and Rhodophyceae like Ectocarpus, Polysiphonia, Sargassum, Ulva. arvind wasnik
  • 9. GENERAL CHARACTERS Terminologies used for Aquatic Algae: Habit Habitat Example 1. Benthophytes Algae remains attached to any substratum ( growing on mud and other bottom ) The Benthic Algae may be Epipelic Epipsammic Grows on Sediments Located on Sand Ex. Oedogonium Annual Perennial Ex. Porphyra Ex. Sargassum Fresh Water are Chara, Nitella Marine are members of Phaeophyceae and Rhodophyceae 2. Epactiphytes Growing along shores of lakes or ponds. Ex. Spirogyra, Chaetophora. 3. Neustonic They grow on water surface Ex. Hydrodictyon arvind wasnik
  • 10. Habit Habitat Example 4.Thermophytes Growing in thermal water can tolerate very high temperature Based on temp. Hypothermae ( Below 18 ‘C) Hliarothermae (18- 30 ‘C) Euthermae (30 -50 ‘C) Aerothermae (50 -70 ‘C) Hyperthermae ( Above 70’C) Majority of thermal algae belongs to Myxophyceae group Ex. Synechococus elongatus, Mastigocladus laminosus 5. Planktophytes Floating Algae. Are of two types: 1.Euplanktophytes: True floating Algae ex. Volvox, Hydrodictyon 2.Tychoplanktophytes: Becomes floating accidentally ex. Oedogonium, Nostoc Ex. Spirulina, Volvox, Euglena, Chlorella, Chlamydomonas etc arvind wasnik
  • 11. ALGAL BLOOM Abundant growth of planktonic algae begin to impart colour to the water, such phenomenon is called Water Bloom as caused due to algae so called as Algal Water Bloom. Formation of blooms depends on temp. increase and nutrient availability. Water Bloom may be Temporary/Permanent Mixed/Pure 1. Temporary & Mixed type are produced by Chlamydomonas, Scendesmus, Chlorella, Ankistrodesmus, Pediastrum etc. 2. Temporary & Pure contains only one species Volvox globator or Chlamydomonas sp. 3. Permanent & Mixed are made up of Anabaena, Anabaenopsis, Microcystis etc. 4. Permanent & Pure a. Trichodesmium sp forms a permanent red water bloom in red sea. b. Microcystis aeruginosa forms permanent blue green water bloom in temple ponds. arvind wasnik
  • 12. Habit Habitat Example 6. Halophytes Growing in saline habitat In salt lakes ex. Chlamydomonas ehrenberghii In salt springs ex. Enteromorpha sp. Dunaliella etc 7. Epiphytes Growing attached on other plants or algae. Epiphytic algae on submerged hydrophytes known as Periphyton Choleocheate in association with Chara & Nitella Cladophora on leaves of Vallisneria & Nelumbo Oedogonium on Hydrilla 8. Epizoophytes Grows on aquatic organisms Cladophora crispata on Snail Shell Characium on Mosquito Larva Protoderma on Turtle Shell arvind wasnik
  • 13. GENERAL CHARACTERS 2. TERRESTRIAL ALGAE Algae that grows on or in soil called as Edaphophytes a. Sapophytes- Algae grows on the soil surface ex. Vaucheria b.Cryptophytes- Algae grows in the soil, fix nitrogen for the soil fertility ex. Nostoc, Anabeana arvind wasnik
  • 14. GENERAL CHARACTERS 3. AERIAL ALGAE Habitat is aerial and are called as Aerophytes Habit Habitat Example 1. Epiphyllophytes Grows on the leaves of terrestrial plants Trentopholia sp on the leaves of Butea monosperma 2. Epiphloephytes or Corticolous Growing on the Mosses, Liverworts and on the Barks Ex. Pleurococus, Microcolous. 3. Epizoophytes They grow on the body of terrestrial animals Ex. Cyanoderma on the hairs of Sloth Bear 4. Lithophytes Growing attached to stones and rocky surface a.Epilithic- On rock surface ex. Calothrix b.Endolithic- Inside the rock or inside the skeleton of corals ex. Dalmatella c.Chasmolithic- Grows in rock fissures ex. Gleocapsa arvind wasnik
  • 15. GENERAL CHARACTERS 4. Algae of Unusual Habitat A. Cryophytes: Algae grow on Ice or Snow Only on snow- Raphidonema Only on ice- Ancyclonema On both ice & snow- Trachiscia Not true cryophytes-Phormidium In Europe some mountain become green colour due to Raphidonema Yellowishgreen due to Chlamydomonas yellowstonensis Red colour due to Chlamydomonas nivalis (Arctic & Alpine Region) Brown colour due to Ancyclonema nordenskioldii Yellow colour due to Protoderma Green colour due to Scotiella arvind wasnik
  • 16. GENERAL CHARACTERS B. Symbionts Some Algae live in association with certain Plants and Animals 1. Endophytic Algae: With Plants Nostoc in Anthoceros Anabeana cycadeae in the corolloid root of Cycas BGA Cyanailae in Protozoa 2. Endozoic Algae: With Animals Zoochlorella in Hydra viridis Trochisia sp. In Rana agilis Oedogonium undulatum in Insect Larva Oscillospira sp. In Guinea Pig arvind wasnik
  • 17. GENERAL CHARACTERS C. Parasitic Algae Some BGA like Simonosiella sp. are found as parasite in the Human Intestine Cephaleuros virescens grows on the leaf of Thea sinensis (Tea Plant) and cause the disease known as Red Rust arvind wasnik
  • 18. GENERAL CHARACTERS III. THALLUS ORGANIZATION Vegetative body of Algae is called as thallus It is not differentiated in to Root, Stem and Leaf, so algae are simple plants arvind wasnik
  • 19. GENERAL CHARACTERS A. Unicellular- All vital function of life performed by a single cell, these are of 1. Flagellated/Motile 2. Amoeboid/Rhizopodial 3. Non-Motile/Coccoidal 1. Flagellated/Motile Form: Have flagella One Flagella ex. Trachelomonas, Chromulina Two Flagella- When both flagella are equal in size is called Isokont ex. Chlamydomonas, Haematococcus When both flagella are unequal in size called Hetrokont ex. Gonyostomum arvind wasnik
  • 20. GENERAL CHARACTERS 2. Amoeboid/Rhizopodial Form Having protoplasmic projection called pseudopodia ex. Chrysamoeba 3. Non Motile/Coccoidal Form Lack cell wall and no locomotary organ ex, Diatoms, Chlorella arvind wasnik
  • 21. GENERAL CHARACTERS B. MULTICELLULAR THALLUS: Multicelled Thallus 1. Colony: It is formed by the aggregation of individual cells a. Coenobium- A colony with definite numbers of cells and having a constant shape and size Non Motile : Aggregations of non-motile cells in the form of a colony (non-motile) are common only in Chlorophyceae. Here the cells are, more or less, fused together (e.g., Hydrodictyon) or connected by mucilaginous threads (e.g., Dictyosphaerium) and the colony may be of various shapes. It may be plate like e.g.. Scenedesmus or net-like as in Hydrodictyon. arvind wasnik
  • 22. Motile Motile flagellated cells aggregate together to form motile colonies. Colonies vary in shape and size and in the number of cells. The colonies are either “plate-like” (e.g., Gonium) or spherical (e.g., Volvox). arvind wasnik
  • 23. arvind wasnik Pamelloid In a large number of genera this habit is a permanent one e.g., Tetraspora (Chlorophyceae), Phaeocystis (Chrysophyceae) or is a temporary phase, in the life- cycle e.g., Chlamydomonas (Chlorophyceae) Chromulina, (Chrysophyceae). The habit is named after the genus Palmella (Palmeflaceae, Chlorophyceae) Here the individual lion-flagellated cells have mucilaginous sheaths around them and are enveloped in a common gelatinous matrix of indefinite shape which may be microscopic or macroscopic in size.
  • 24. arvind wasnik Dendroid A variation of the palmelloid condition is seen in dendroid colonies. Here the mucilage is produced locally, generally at the base of the cell. Dendroid forms are seen e.g. Prasinocladus (Chlorophyceae), Mischococcus (Xanthophyccae) and in Chrysophyceae and Euglenineae
  • 25. 2. Filamentous Forms:  the division of the single cell into many daughter cells with septa between the divided cells a filamentous type of construction would be formed. (i) Un-branched Filaments:  Simple un-branched filaments are found in many forms. They are either free-living e.g., Spirogyra or attached, at least initially e.g., Oedogonium, or aggregated in colonies e.g., Nostoc arvind wasnik
  • 26. (ii) Branched Filaments:  (i) Simple  (ii) Heterotrichous  (iii) Pseudoparenchymatous (i) Simple A simple branched filament with dichotomous branching pattern and a basal attaching cell, holdfast or hapteron is common with many types e.g., Cladophora. A peculiar form of branching, known as ‘false’-branching is observed in Cyanophyceae e.g., Scytonema arvind wasnik
  • 27. arvind wasnik (ii) Heterotrichous This most highly evolved type of plant-body, showing a good amount of division of labour. The plant-body consists of two distinct parts: (1) A basal or prostrate creeping system, and (2) An erect or upright system. The prostrate system is attached to some substratum, grows apically and gives rise to numerous photosynthetic and rhizoidal filaments. Rhizoidal filaments sometimes penetrate the substratum . The erect system develops from the prostrate system and is composed of one or more and usually branched photosynthetic filaments. In Stigeoclonium and Trentepohlia these two systems are equally developed and easily distinguished.
  • 28. Whereas in Coleochaete (Chlorophyceae) and Ascocyclus (Phaeophyceae) the prostrate system is highly elaborated and the erect system is reduced. This gives the body a discoid type of appearance. On the other hand, in many species of Ectocarpus, the prostrate system is reduced, and the erect system is well developed. This gives the body a crust or cushion type of appearance. In many cases the reduction of one system has gone to the limit of practical elimination. Thus in an endophytic species, Endoderia and in Chaetopeltis (Chlorophyceae) only the prostrate system is developed. Complete absence of prostrate system is noticed in Microthamnion. arvind wasnik
  • 29. (iii) Pseudoparenchymatous forms: As indicated by the term ‘pseudo’ = false, the plant body gives the appearance of parenchymatous construction. The pseudoparenchymatous structure is a secondary development, close association of cells is a result of interweaving of filaments. Intercellular connections may be densely packed and firmly coherent (e.g., Dumontia, Rhodophyceae) or, the association may be loose and can easily be separated by pressure (e.g., Castanea, Phaeophyceae). Two types are: (1) uniaxial construction = a single colourless central axial filament e.g., Batrachospermum (2) multi-axial = many filaments e.g., Polysiphonia arvind wasnik
  • 30. 5. Siphonaceous Forms:  In a number of algae, belonging to Siphonales e.g., in Vaucheria, Botrydium, the growth of the plant body takes place without the usual cross-wall formation except during formation of reproductive organs. Thus a ‘tube’- like multinucleate structure, or a coenocyte, is produced. arvind wasnik
  • 31. 6. Parenchymatous Forms: Parenchymatous thallus organization also is a modification of the filamentous habit, with cell division in more than one plane. The parenchymatous thalli may be ‘leaf-like’ or foliose, tubular or highly developed structure. Foliose or Tubular thalli are formed by the division of the cells two or three planes. Common examples of foliose structures in Viva (Chlorophyceae), Porphyra (Rhodophyceae). The example of tubular structure is Enteromorpha (Chlorophyceae). arvind wasnik
  • 32. Reproduction Found in Algae There are three common methods of reproduction found in algae – (i) vegetative, (ii) asexual, and (iii) sexual.  1. Vegetative reproduction: This may be of several types. (i) By cell division: The mother cells divide and the daughter cells are produced, which become new plants. This is exclusive type of reproduction in Pleurococcus, some desmids, diatoms, Euglena, etc. (ii) Fragmentation: The plant body breaks into several parts or fragments and each such fragment develops into an individual. This type of vegetative reproduction is commonly met within filamentous forms, e.g., Ulothrix, Spirogyra, etc. The fragmentation of colonies also takes place in several blue green algae, e.g., Aphanocapsa, Aphanothece, Nostoc, etc. arvind wasnik
  • 33. arvind wasnik (iii) Hormogone formation: When the trichomes break in small pieces of two or more cells, such pieces are called ‘hormogones’. Each hormogone develops into a new plant, e.g., Oscillatoria, Nostoc, etc. (iv) Hormospores or hormocysts: They are thick-walled hormogones, and produced in somewhat drier conditions. (v) By adventitious thalli: Certain special structures of thalli are formed which help in vegetative reproduction. The well known propagula of Bryopsis, Sphacelaria and Nereocystis are good examples. (vi) By primary secondary protonema: Such thread-like vegetative bodies develop in the case of Chara, which help in reproduction. (vii) Tubers: Usually these bodies are rounded and filled up with abundance of starch. Each body may give rise to a new plant, e.g., Chara. (viii) Starch or amylum stars: Such special star-shaped, starch filled bodies give rise to new plants frequently reported from Chara.
  • 34. arvind wasnik (ix) Bulbils: Small bud-like structures. Usually develop on the rhizoids of Chara are called bulbils. Each such bulbil may develop into a new plant. (x) Akinetes: In most of the Chlorophyceae members, the Akinetes are developed. Usually the protoplast of each cell converts in a single akinete. Sometimes they are formed in chains. Each akinete may develop into a new plant, e.g., Oedogonium, Ulothrix, etc. 2. Asexual reproduction: Usually the protoplast of a cell divides into several protoplasts and thereafter they escape from the mother and develop into new plants. (i) By zoospores: The zoospores are formed from certain older cells of the filaments. The cytoplasm divides to form zoospores which are escaped from the mother cell. They are always formed in favourable conditions. The zoospores are always motile. They may be (i) biflagellate, (ii) tetraflagellate, (iii) stephanokontean type of zoospores, e.g., Oedogoniales and (iv) compound zoospores, e.g., Vaucheriaceae
  • 35. arvind wasnik (ii) By aplanospores: When motile phase of zoospores is eliminated, the bodies are called aplanospores. The aplanospores develop in unfavourable conditions. Each such spore is surrounded by a wall. (iii) By hypnospores: Actually they are very thick-walled aplanospores and develop only in adverse conditions, e.g., Pediastrum, Vaucheria. (iv) Palmella stage: Here the successive generations of divided cells are gelatinized and a thick mucilaginous envelope develops, e.g., Chlamydomonas, Ulothrix, etc. (v) Autospores: They are just like aplanospores except that they are smaller in size. They resemble in shape to mother cell except in size. Each autospore gives rise to a new plant. Such autospores are reported from many Chlorococcales. (vi) Endospores: In many blue green algae and Bacillariophyceae, the endospores are formed within the cells. On the approach of favourable conditions, each endospore develops in a new individual. (vii) Exospores:
  • 36. arvind wasnik (viii) Carpospores: They are found in the carposporophytes of red algae (Rhodophyceae). Each such spore develops in a new individual. (ix) Tetra spores: (x) Monospores: These spores develop within monosporangia. Each spore gives rise to a new plant, e.g., many members of Rhodophyceae (Bangia, Porphyra, Porphyridium, etc). (xi) Paraspores: Such spores are reported from many members of Rhodophyceae. Each spore develops into a new plant. (xii) Statospores: They are found in Xanthophyceae and Bacillariophyceae where they act as perennating bodies. (xiii) Daughter colonies: In many Volvocales and Chlorococcales, the daughter colonies are developed asexually, e.g., Volvox, Hydrodictyon, Pediastrum, etc. (xiv) Gongrosira stage of Vaucheria: In the aseptate filaments of Vaucheria, the protoplast divides into several parts, several hypnospores or cysts are produced and the whole filament looks like an algal form ‘Gongrosira’. (xv) Microspores: They are produced in many Bacillariophyceae.
  • 38. arvind wasnik It is greatly advanced method of reproduction and not known in Myxophyceae (blue green algae). There are two main types, i.e., (i) isogamy and (ii) heterogamy. (i) Isogamy: The fusion of similar motile gametes is found in many species. Usually the gametes taking part in fusion come from two different individuals or filaments, sometimes these gametes come from two different cells of the same filament. Thousands of gametes come and aggregate in clumps. (See Fig. 3.8). (ii) Heterogamy: The fusion of dissimilar gametes is called heterogamy. There are variations of it. (a) Anisogamy: The motile gametes taking part in fusion may either differ in size (morphological anisogamy) or physiological behaviour (physiological anisogamy). (b) Oogamy: In this case, the male antherozoid fuses with the female egg. This fusion may be of primitive type as found in Cylindrocapsa, or advanced type as in Oedogonium, Vaucheria, Chara, Polysiphonia, etc.
  • 39. arvind wasnik (iii) Aplanogamy or conjugation: It implies the fusion of two non-flagellate amoeboid gametes (aplanogametes). They are morphologically similar but physiologically dissimilar, e.g., order Conjugales. In fresh water algae, the sexual reproduction is best means of perennation because it is followed by the formation of thick-walled zygote or oospore. Parthenogenesis: The female gametes convert into zygotes without fusion. The resultants are called azygospores or parthenospores and the phenomenon ‘parthenogenesis’, e.g., Spirogyra, Oedogonium and many others. Autogamy: In this phenomenon, the fusion of the daughter protoplasts or of the divided nuclei of a cell without liberation takes place. This process is known in many diatoms and colour-less dinoflagellates.