ALGAE - GENERAL CHARACTERS

1. SUBMITTED BY
JISNA .T
BSc. BOTANY
Govt.college chittur

2. ACKNOWLEDGMENT
I take this opportunity to express my gratitude
in few words and respect to all those who
helped me in the completion of this project. It
is my humble pleasure to acknowledge my
deep sense of gratitude to my teachers for
valuable support , constant help and guidance
at each and every stage

3. GENERAL FEATURES -
ALGAE
TOPIC

4. CONTENT
Definition of algae
Structure of algae
Algal flagella
Algal cell structure
Habitat
Organization of thallus
Pigmentation
Nutrition
Food Reserve

5. ALGAE

6. ALGAE - STRUCTURE
THALLUS – Undifferentiated plant body
BLADE – leaf like flattened portion
PNEUMATOCYST –
gas filled chambers
STIPE – seaweeds having
support for holding
blades
HOLD FAST – Root like structure

7. BLADDERS HOLDFASTS

8. ALGAL FLAGELLA
They are the fine, protoplasmic , whip like threads in motile
algae – flagella
Isokont – equal in length
Heterokont – unequal in length
2 kinds : whiplash – smooth surface [ acronematic ]
tinsel – feathery appearance [ pantonematic ]
Blepharoplast – a single granule at the base of each
flagellum
it has typical 9 + 2 pattern of arrangement of microtubules

9. ALGAL CELL
3 Kinds :
1.prokaryotic : blue green algae
2.eukaryotic : other groups
3.mesokaroytic : Dinophyceae

10. habitat

11. A] hydrophytes
1. Planktophytes – floating & drifting algae
Euplanktophytes – non attached e.g., diatoms
Tachyplanktophytes – initially attached & later free
e.g., zygnema
2. Benthophytes – fixed or attached bottom dwelling algae
Periphytes - attached to submerged aquatic plants
e.g., nostoc
Lithophytes – attached to rocks & stones
e.g., polysiphonia

14. 3. Epactiphytes – fresh water algae growing along the banks
of ponds & lakes e.g., oedogonium
4. Thermophytes – inhabiting hot springs e.g., blue green algae
5. Halophytes – inhabiting saline waters e.g., pediastrum
6. Epiphytes – attached to living plants e.g., coleochaeta
7. Epizoophytes – attached to living aquatic animals , such
as turtles e.g., cladophora

15. LITHOPHYTES
HALOPHYTES

16. THERMOPHYTES
EPIZOOPHYTES

17. 1. Saphophytes – soil surface e.g., botrydium
2. Cryptophytes – sub surface soil e.g., nostoc
3. Lithophytes - moist rocks , wet walls e.g., blue green algae
4. Psammophytes – sand , along sanndy shores
B] EDAPHOPHYTES

19. The algae adapted for aerial mode of life .
they grow on the leaves & bark of trees , on the bodies of
animals
1. Epiphyllophytes – remains attached to leaves of
trees e.g., phyllosiphon
2. Epiphloeophytes – grows on tree bark together with
may mosses & liverworts
e.g., haplosiphon
3. Epizoophytes - algae found on the bodies of land
animals
C] AEROPHYTES

20. AEROPHYTES

21. Algae found in snow & ice
Responsible for red snow , green snow , violet snow etc..
D] CRYOPHYTES

22. Algae found within the body of aquatic animals
e.g., zoochlorella in hydra viridis
F] PARASITES
E] ENDOZOOPHYTES
Some algae exist as plant parasites e.g., Caphaleuros viresces
[ parasite of tea ]

25. Algae existing in symbiotic association with other plants
forming lichens
e.g., chlorella with
nitrogen fixing
bacterium azotobactor
G] SYMBIONTS
Oophila amblystomatis - salmander

27. CHLAMYDOMONAS – MOTILE CHLORELLA - NONMOTILE
UNICELLULAR

28. PEDIASTRUM - coenobium VOLVOX COLONY
MULTICELLULAR

29. DINOBRYON – DENDROID FORM
AMORPHOUS

30. CHARA - HETEROTRICHOUS ULVA - PARENCHYMATOUS

31. VAUCHERIA - SIPHONOUS

32. PSEUDOPARENCHYMATOUS -
BATRACHOSPERMUM

33. SIMPLE BRANCHED
UNBRANCHED
PSEUDO BRANCHED

34. PIGMENTATION
3 major categories
based on the chemical & physical properties
1. chlorophyll
2. carotenoids
3. phycobilins

35. 1. CHLOROPHYLL
Fat soluble green pigment
They absorbs blue region & reflects green light
Responsible for green colour of algae
7 different types

37. STROMATOLITES
Cyanobacteria can form rock - like structures in warm tidal areas

39. 2. CAROTENOIDS
fat soluble yellow pigments
accessory photosynthetic pigments
there are 3 main groups :
1. carotenes
2. xanthophyll
3. carotenoid acids

40. CAROTENES
absorbs blue - green light & transmit yellow – red light
non oxygenated
examples : ß carotene , lycopene & flavicine
XANTHOPHYLL
also called carotelos
oxygenated hydrocarbon
examples : lutein , zeaxanthin
Carotenoid acids
formed of a chain of carbon atoms

43. 3. PHYCOBILINS
water soluble
always bonded with protein called phycobiliproteins
blue & red in colour
strongly fluorescent
emits orange or red light after fluorescence
3 main kinds :
1. phycoerythrins
2. phycocyanins
3. allophycocyanins

46. PLASTIDS
Pigments are found in membrane bound organelles
called plastids
except blue green algae – plastids are absent
pigments are found at peripheral cytoplasm
[ chromoplasm ]
plastids are of two types :
leucoplast - colourless
chromoplast - coloured

47. PLASTID FORMS IN ALGAE
Cup Shaped - Chlorella , Chlamydomonas
Spiral - Spirogyra
Girdle - Ulothrix
Stellate - Zygnema
Discoid - Chara
Reticulate - Oedogonium

48. ALGAL NUTRITION
Photoautotrophs - using only inorganic medium for
synthesizing organic foods
Photoauxotrophs - using some organic substance like
thiamine , biotin etc.,
Heterotrophs - do not synthesize organic food from
inorganic substances but solely from
organic constituents .

49. RESERVE FOOD
Chlorophyceae : starch & oils
Xanthophyceae : chrysolaminarin & oils
Bacillariophyceae : volutine & oils
Phaeophyceae : laminarin , mannitol & oils
Rhodophyceae : floridean starch , fats
Cyanophyceae : cyanophcean starch ,
cyanophycin

50. REFERENCES
www.easybiologyclass.com
S.Chand & company ltd publications – botany for
degree students algae – B.R.Vashishta , Dr. A.K.Sinha ,
-1-13
K.K.Bhaskaran , A.R.Ajith Kumar Ramesh . Phycology ,
bryology , pteridology , published by Manjusha
publications