5. INTRODUCTION
680 generas
4000-6000 species
Habitats:• In marine
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In tropical
In warm water
In cooler regions
In fresh water
Eukaryotic
Nutrition mode
• Autotrophic
9.
Cell wall
• Rigid
• Inner component
Cellulose
Another polysaccharide
•Outer mucilaginous layer
Sulfated polymer of galactose – agar or carrageenan
•Some deposit calcium carbonate - family –
Corallinaceae (Coralline algae)
Cell structure
10. Absence of flagella and centrioles
Floridean starch as a storage product
Chloroplast
• unstacked plastids in thylakoids
•Pigment
Chlorophyll a,phycoerithrin,phycocyanin
allophycocyanin
presence of the phycobilin or phycoerithin
11. STRUCTURAL COMPLEXISITY OF
Gracillaria
From of thalli
•Often fleshy thalli
•Cylindrical or terete
•Compressed or flattened
•Foliose
Branching
•Alternate
•Di or trichotomous
•Secund
•Irregular
12. Constriction of branches
• frequently Gracilaria shows a constriction at the point
where a lateral branch joins a main axis.
Branch apex
•Attenuate
•Rostrate
•Tapering
•Apiculate
•Obtuse
•Blunt
13. Types of spermatangial conceptacles
•Chorda type-superficial
•Textorii type-shallow cavity
•Verrucose type-deep pot like cavity
•Polycavernosa type-compound verrucosa type
Characteristics of cystocarps
•Form
•Basal constriction
•With or without rostum
Anatomy of cystocarp
•Pericarp
•Gonimoblast cells
•Carposporangia
•Absorbing filament
Types of cystocarps
14. Order – Nemalionales
Filamentous or uniaxial multicellular
Stem like thalli often dichotomously branched and
gelatinous in texture
Batrachospermum
16. Order- Gelediales
Thalli is cylindrical and wiry or flattened
Usually pinnately branched
Usually pseudo-parenchymatous
17. Order - Cryptonemales
Plants form
Dichotomously branched structure
Growing in tangled
Small clumps
Branches composed of rigid
Cylindrical segments with flexible joints
18. Order- Gigantinales
Crustose to fruticose
Foliose types with thin, broad fronds
fruticose types with flattened
Usually dichotomously branched
Often fleshy thalli
Tissues as in cryptonemiales
22. Life Cycle of Polysiphonia
Isomorphic
Gametophytes:•heterothallic
•male gametophytes
•female gametophytes
Spermatia:•unite with the tricohogyne
spermatangia
23. Zygote:•oogamous
•auxillary cell become zygote
•grows in a carposporophyte
Carpospores:•type of mitospores
•produce by carposporophyte
•settle out of water column
•grow in to tetrasporophyte
carcosporangia
24. Tetrasporsphytes:•Isomorphic to gametophyte
•Produce tetrasporangia in which
meiosis takes place
Tetrasporangia
Tetraspores:•produce by meiosis
•shed to the water
•settle out of the water column
•grow up in to gametophytes
34. Order-cereniales
Slender
Filamentous or unisexual bush like plants
lacking clear cut differentiation of cortex
and medulla tissues
Simpler anatomy accompanied by more
complex reproductive structure is
characteristic of this order