Write a note on the different types of thallus organizations found in algae with suitable diagrams.
Answers
Answer:
Explanation:
1. Unicellular Type:
(a) Unicellular Amoeboid Forms or Rhizopodial Forms:
(Fig. 1).
(b) Unicellular Motile (Flagelloid) Forms:
(Fig. 2).
(c) Unicellular Non-motile (Protococcoidal) Forms:
(Fig. 3).
2. Aggregates:
(a) Palmelloid Habit:
(Fig. 4).
(b) Dendroid Forms:
(Fig. 5 A, B).
(c) Rhizopodial Forms:
3. Colonial Forms:
The colony may be (a) motile or (b) non-motile.
(a) Motile Colonial Forms:
(Fig. 6).
(b) Non-Motile Colony:
(Fig. 7).
4. Filamentous Forms:
(i) Un-branched Filaments:
(Fig. 9), (Fig. 8 B).
(Fig. 8 A).
(ii) Branched Filaments:
Branched filamentous structures may be put into three categories:
(i) Simple,
(ii) Heterotrichous
(iii) Pseudoparenchymatous.
(i) Branched Simple:
(Fig. 9).
(Fig. 10).
(ii) Heterotrichous:
The plant-body consists of two distinct parts:
(1) A basal or prostrate creeping system, and
(2) An erect or upright system.
(Fig. 11)
(iii) Pseudoparenchymatous forms:
Two types are recognised in the construction of the pseudoparenchymatous thallus. The body may have (1) a single colourless central axial filament (uniaxial construction) or (2) many filaments (multi-axial) around which photosynthetic filaments are supported (Fig. 12, 13).
5. Siphonaceous Forms:
(Fig. 14). In other Siphonales, two basic patterns are seen.
In one the siphon has become increasingly large and branched (e.g., Caulerpa) and the other is an intricate system of interwoven vesicles and tubes (e.g., Codium).
6. Parenchymatous Forms:
(Fig. 15 A, B).