What is the function of hormogonia?
Hormogonia are motile filaments produced by many filamentous cyanobacteria that function in dispersal, phototaxis and the establishment of nitrogen-fixing symbioses.
What is thallus Oscillatoria?
The thallus is an unbranched, cylindrical, narrow or broad filament, entirely without or with barely perceptible watery, hyaline and mucilaginous sheath. Each filament consists of a single row of cells in the form of short cylinders, which may even be shorter than they are wide.
What does Oscillatoria look like?
Description: Oscillatoria is a filamentous blue-green alga that can be found throughout North Carolina. Its filaments are motile and weave into thin mats that coat sediment and other submerged surfaces. The bright blue and blue-green mats are commonly described as looking like spilled paint.
Does Oscillatoria have cell wall?
The cells of Oscillatoria are prokaryotic. . The cell wall is firm and is composed of hemicellulose and pectin.
How are hormogonia formed in oscillatoria?
Oscillatoria reproduces by fragmentation, facilitated by dead cells which separate a filament into separate sections, or hormogonia, which then grow. Oscillatoria uses photosynthesis to survive and reproduce.
What are hormogonia how are they formed?
Hormogonium is part of the trichome between two heterocysts or between two dead cells, such segments of the filament are formed due to the death of cells along the trichome. These slip out of the mucilaginous sheath and grow into new filaments.
Is Oscillatoria unicellular or multicellular?
Oscillatoria annae include unicellular, colonial and filamentous forms some filamentous cyanophytes form differentiated cells called heterocyst, that are speciallized for hydrogen fixation, and resting or spore cells called aconites.
Is Oscillatoria unicellular or colonial?
Does Oscillatoria have chlorophyll?
In addition, they contain various yellowish carotenoids, the blue pigment phycobilin, and, in some species, the red pigment phycoerythrin. The combination of phycobilin and chlorophyll produces the characteristic blue-green colour from which these organisms derive their popular name.
What is the function of heterocysts in cyanobacteria?
A heterocyst is a differentiated cyanobacterial cell that carries out nitrogen fixation. The heterocysts function as the sites for nitrogen fixation under aerobic conditions. They are formed in response to a lack of fixed nitrogen (NH4 or NO3).
What is hormogonia in Oscillatoria?
Oscillatoria forms long filaments of cells which can break into fragments called hormogonia. The hommgonia can grow into a new, longer filament. Breaks in the filament usually occur where dead cells (necridia) are present. In some cases, hormogones form separating discs at breaking points.
What are the characteristics of Oscillatoria?
Oscillatoria – Classification , Occurrence , Structure and Reproduction. Its trichomes are unbranched filaments. They are covered by very thin mucilaginous sheath. All cells of a trichome are similar in shape except apical cells. The apical cells are convex at the tip. All other cells arc broader and cylindrical.
What is the mode of reproduction in Oscillatoria?
Aseuxal and sexual reproduction is absent in Oscillatoria. Oscillatoria reproduces by fragmentation. Oscillatoria forms long filaments of cells which can break into fragments called hormogonia. The hommgonia can grow into a new, longer filament. Breaks in the filament usually occur where dead cells (necridia) are present.
What is the mode of reproduction of the phylum hormogonia?
Reproduction is by fragmentation in which dead concave cells (separation disks) separate sections of the filament (hormogonia). When present, the mucilage sheath is very thin.