[Biology Class Notes] on Batrachospermum Pdf

Batrachospermum is a type of algae that grows in freshwater. It lives in transparent, cool, and fast-moving streams. Plants in deep water are dark violet or reddish in color. The shallow-water species, on the other hand, are olive green. The color of pigments is affected by the strength of light. The substratum is bound to the thallus.

 

Batrachospermum Classification

 

Occurrence

That’s one of the freshwater Rhodophyceae species. This alga can be found in slow-moving streams, as well as along the shores of lakes and ponds. It’s more common in well-oxygenated waters. Colors include blue-green, olive-green, violet, and reddish. Because of the variations in light intensity, the color changes. The species that develop in deep water appear reddish or violet in color, while those that grow in shallow water are olive-green. Frogspawn is another name for the alga. To the naked eye, the plants look mucilaginous, moniliform, or beaded.

 

General Structure

Vegetative Structure

The adult plant’s thallus is soft, dense, and filamentous. It has a lot of branches and is gelatinous. A single row of broad cells makes up the central axis. Upon that axis, whorls of branches with limited growth evolve. These filamentous, dichotomously arranged branches are filamentous. The main axis has a corticated appearance. A series of elongated cylindrical cells make up this structure. It is divided into two categories: nodes and internodes.

 

From the Nodes the Two Groups of Branches

• Branches of Limited Growth: These emerge in whorls from the nodes. Such branches grow for a while before becoming long hairs. Their cells were arranged in a bead-like pattern. A whorl’s branches were of the same length. As a result, they form globos structure glomerulus.

• Branches of Unlimited Growth: Such branches develop from the imsal cells of limited-growth branches. These are often corticated and divided into nodes and internodes. From their nodes, branches of minimal growth emerge. Their cells become longer in comparison.

 

The cells have no nuclei. Two-layered cell walls keep their cells in check. The outer layer is made up of pectic compounds, while the inner layer is made up of cellulose. Within cells, pit connections exist. There are several irregular chromatophores in a cell. Phorerythrin, phycocyanin, and some other photosynthetic pigments such as chlorophyll-a, Carotene, chlorophyll b, and Xanthophyll are among its pigments. A single pyrenoid is present in each chromatophore. The axis’ central cells are linked by cytoplasmic connections. Floedean starch is a food ingredient that has been set aside.

 

Components of the Cell

The cells have no nuclei. Two-layered cell walls keep their cells in check. The outer layer is made up of pectic compounds, while the inner layer is made up of cellulose. Within cells, pit connections exist. There are several irregular chromatophores in a cell. Phorerythrin, phycocyanin, and some other photosynthetic pigments such as chlorophyll-a, Carotene, chlorophyll b, and Xanthophyll are among its pigments. A single pyrenoid is present in each chromatophore. The axis’ central cells are linked by cytoplasmic connections. Floedean starch is a food ingredient that has been set aside.

 

Growth

• Limited-growth branches are formed as a single cell at the apex of the main clament grows. The cell undergoes transverse division. It hacked away at cells on the backside. Four small cells are cut off by each of these cells. The initials of these cells become the side branches’ initials. Such kind initials are divided numerous times. These lateral cell groups produce a coster of small branches. It creates a beaded pattern on the vine. A glomerulus is a group of side branches. Whorls are formed by these branches.

• Central Axis Cell Elongation: The central axis cell elongates dramatically. As a result, lateral cells begin to differentiate from one another. As a result, on the axis, they create a node-like structure.

• Formation of Pseudocortex: Filaments are generated by the cells at the nodes as they move downward. They encircle the central cells before they reach the next node. As a result, a loose covering forms around the central axis. Pseudocortex is the term for this loose coating.

• Formation of Unrestricted-growth Branches: Apical cells may be one or more cells on each node. Like the main axis, this cell develops lateral branches with infinite growth potential.

 

Batrachospermum Reproduction

• Antheridia or Spermatangia: Antheridia or spermatangia are the male sex organs. They are a single-celled structure. The mature spermatogonium has a thick wall, is colorless, and has a rounded shape. Spermatangia are made singly, in pairs, and in four-person groups. Antheridium protoplast transforms into just a single non-motile spermatium. The antheridial wall fractures, allowing sperm to escape.

• Carpogonia: Carpogonia is the female reproductive organ. Carpogonia is a single-celled organism. It is made up of an elongated cell that is present at the base. Trichogyne refers to the larger upper section. Mirophore refers to the lower globular part. Ascocarp refers to the branch that bears the carpogonium. The ascocarp is made up of four cells. Carpogonium is formed by the terminal cell. Mirophore contains the nucleus of an egg. The nucleus of an egg is enclosed by cytoplasm and transforms into an egg. A constriction separates the trichogyne from the mirophore. Trichogyne is a sperm-receiving organ.

 

Batrachospermum Life Cycle

The spermatia that are not motile float in the water. The trichogyne is approached by a large number of spermatia. The trichogyne is attached to one of the spermatia. The contact wall dissolves, and one of the spermatium’s two nuclei flows via this hole into the trichogyne, fusing with the female egg and developing into the zygote within the basal swollen region of the carpogonium. The trichogyne then shrivels down until it reaches the constriction between trichogyne and carpogonium. At the same time, across wall forms at this stage.

 

Germination of the Zygote

The zygote’s diploid nucleus separates meiotically, yielding two haploid nuclei. After that, one of the two nuclei travels into the zygote’s lateral protrusion. This protrusion is separated from the rest of the zygote by a wall, and the gonimoblast initial
is shaped in this way. The other daughter nucleus divides many times, resulting in a large number of gonimoblast initials. The gonimoblast branches out, and the terminal cells of such branched gonimoblast grow into carposporangia. Each carposporangium generates a unique single haploid carpospore that is rounded. The cystocarp or carposporophyte is a structure of gonimoblast filaments, carposporangia, and carpospores.