Table of Contents
The word Charophyte originates from a Latin word which when broken into two words consist of “chara” called the root and “phyta” means plant. Charophyta is a phylum consisting of green algae, which are found in freshwater. Within the phylum of Charophyta, another phylum did exist, the phylum Chlorophyta and both of were photosynthetic eukaryotes, which were green in color, due to the chlorophyll, which consists of thylakoids.
Charophytes possess chlorophyll A and B along with other pigments like carotenoids. The storage of sugar is in the form of starch in Charophyta and Chlorophyta. However, Charophytes differ from chloroplast in the formation of cell wall during division and the assembly of cell plate with the use of phragmoplast.
Enzymes like superoxide dismutase, glycolate oxidase and flagellar peroxidase are present in Charophytes. The progenitor of Charophytes are supposed to be the embryophytes, as they resemble in structure.
According to the Hoek Mann and Jahns system, charophytes have been categorized into the class Chlorophyta. Although in the modern classification, which was given by Lelieaert, chlorophytes and charophytes have been placed separately. In the Streptophyta of Viridiplantae is the charophytes placed along with embryophytes.
Viridiplantae are a group of green plants, which possess chlorophyll a and b, but not phycobilin and in their cell wall contain cellulose and the storage is starch is in the plastids. As more species are being discovered, changes in the taxonomy classification of organism is ought to occur, resulting in modern classification system like the NCBI taxonomy database.
The green algae is formed from both, the Chlorophytes as well as the Charophytes. They appear green in color due to the presence of chlorophyll in the cell wall which is quite prominent. The storage of food in Charophytes is in the form of starch. Cell wall is composed of cellulose in these class of organisms.
The phylum Charophyta consists of the sub-groups and which are;
- Embryophyta is also added to the list of this sub-groups
Charophyte Evolution and Phylogeny
From the green algae, charophytes have been originated. The green algae is believed to be progenerated from endosymbiotic theory, which states that from prokaryotes, eukaryotes have been developed. The development of prokaryote to a plastid, resulted in the formation of green algae. This green algae further formed chlorophytes and charophytes. The charophytes further evolved and formed another group called the embryophytes. The combination of Embryophytes and Charophyta resulted in the development of Streptophyta.
Biological Importance of Charophyte
The source of photosynthetic output is the green algae. As these organisms are the one which generates food, they are known as the producers and these organism will serve as food source to other organism which are the heterotrophs, which reside in the marine habitat.
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