Affinities of Anthoceros with other members.

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Affinities of Anthoceros with other members. Anthoceros shows affinity with algae, members of Hepticopsida and Bryopsida of Bryophyta and Pteridophyta.The affinity and relationship of Anthoceros with green algae lies in the presence of a single large chloroplast together with a pyrenoid in cach cell of the gametophyte and in the formation of biciliated sperms. Anthoceros shows affinity with members of Hepaticopsida such as Riccia, Marchantia, etc. in the construction and structure of sex organs and in the apical growth of the thallus.It has affinity with members of Bryopsida i.e. Polytrichum, in the structure such as presence of columella, reduction of sporogenous tissue etc. and development of sporogonium. The spore production from amphithecium resembles the condition of that in Sphagnum. Anthoceros also shows sunken archegonium and development of antheridium from hypodermal initial cell like Pteridophyta. Highly developed sporophyte having photosynthetic tissue, functional stomata, i...
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Oedogonium Practical

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 Sample A2

1. Supplied specimen appears as unbranched or sparingly branched filaments. The thallus is multicellular, filamentous and unbranched. Filaments are typically composed of cylindrical cells arranged end-to-end.

 

2. The filament is differentiated into three types of cells according to their position : (i) basal, (ii) intercalary and (iii) apical.

 

3. The basal cell of a filament serves as an anchor. The lowest section of the holdfast might take the form of either a disc or a finger-like structure. The upper portion is predominantly wide and curvaceous. The basal region of the cell typically lacks chlorophyll and is consequently devoid of green coloration, in contrast to the other cells within the filament.

 

4. The cell located at the apex of the filament is referred to as the apical cell. The free surface of the object is curved.

 

5. The cells located between the basal and apical cells are known as intercalary cells. These have characteristic cellular morphology. The average cell has a cylindrical shape. The cell wall is characterized by its substantial thickness and consists of three distinct layers.

 

6. A reticulate chloroplast runs parallel to the cell's long axis inside the cell wall.

 The chloroplast contains a large number of pyrenoids.

 

7. The cell contains only one nucleus. The nucleus is positioned adjacent to the cell wall and is supported by slender and fragile cytoplasmic strands.

 

8. Mature and old cells show 'cap cells' at their upper end.

……………………………..Hence The specimen is Oedogonium  sp

 

Systematic Position:

Division: Chlorophyta

          Class: Chlorophyceae

                  Order: Oedogoniales

                        Family:  Oedogoniaceae

                                    Genus:  Oedogonium





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