What does a Hydrodictyon do?
The extensive nets or mats of Hydrodictyon serve as important refugia for aquatic invertebrates such as cladocerans, leeches, snails, and some beetle larvae. The life cycle of this green alga is well studied, with asexual propagation occurring via zoospores formed simultaneously en masse.
What shape is the chloroplast of Hydrodictyon?
It is flat and saucer shaped and its maximum size is generally 20-30 cm. Rarely it may reach up to a length of 60 cm. The mature net of coenobium is made up of a few hundred to several thousand cells. These cells are joined at the end and form pentagonal or hexagonal structures.
What is the structure of spirogyra?
Named for their beautiful spiral chloroplasts, spirogyras are filamentous algae that consist of thin unbranched chains of cylindrical cells. They can form masses that float near the surface of streams and ponds, buoyed by oxygen bubbles released during photosynthesis.
What type of algae is Hydrodictyon?
filamentous green algae
water net, (genus Hydrodictyon), genus of filamentous green algae (family Hydrodictyaceae) sometimes found on the surface of quiet freshwater bodies.
Why is Hydrodictyon called water net?
The water net (genus Hydrodictyon) is a taxon of green algae of the family Hydrodictyaceae. Its name water net comes from its shape, which looks like a netlike hollow sack. It can grow up to several decimetres.
Which green algae has star-shaped chloroplasts?
Zygnema Green Algae
A common sight floating atop stagnant water, algae of the genus Zygnema can be identified microscopically by its two star-shaped chloroplasts per cell.
Which algae has discoid shaped chloroplast?
The chloroplast is lens-shaped, oval, discoid,cup-shaped, girdle shaped, reticulate, plate-like, ribbon-shaped, or spiral. Chlamydomonas is unicellular green algae. The shape of Chlamydomonas chloroplast is cup-shaped….Cup shaped chloroplast is found in:
| Chloroplast shape | Examples |
|---|---|
| Reticulate | Oedogonium |
| Ribbon shaped | Ectocarpus |
Do Hydrodictyon have flagella?
Reproduction in hydrodictyon Asexual reproduction takes place by biflagellated (having two flagella) zoospores formed by the thousands inside a cell.
What is the purpose of oscillatoria?
Oscillatoria uses photosynthesis to survive and reproduce. Each filament of oscillatoria consists of trichome which is made up of rows of cells. The tip of the trichome oscillates like a pendulum….
| Oscillatoria | |
|---|---|
| Domain: | Bacteria |
| Phylum: | Cyanobacteria |
| Class: | Cyanophyceae |
| Order: | Oscillatoriales |
Which algae have ribbon shaped chloroplast?
Spirogyra
Spirogyra has thin and flat ribbon-shaped chloroplasts. These chloroplasts are spirally coiled in the structure. The chloroplasts present in Spirogyra have one or more pyrenoids present over them.
What is the shape of chloroplast present in Volvox?
Like Chlamydomonas, each spherical or ovoid cell has two equal flagella with a pair of contractile vacuoles at their base and a large cup-shaped chloroplast with a single pyrenoid.
What is discoid chloroplast?
Discoid. Discoid-shaped chloroplast is found in higher plants, whereas cup-shaped chloroplast is found in the green algae Chlamydomonas. Ulothrix has girdle-shaped chloroplasts and Chlorophyceae have reticulate chloroplasts.
What is the shape of chloroplast in Chlorella?
The chloroplasts are parietal, cup-shaped, or plate-like, and sometimes bear pyrenoids.
What is the name of asexual reproduction method Spirogyra?
fragmentation
The process of asexual reproduction in Spirogyra is known as fragmentation, where the body of spirogyra when matures will get break into many smaller pieces or fragments due to strong water current.
What is polyhedron in Hydrodictyon?
The zygospore wall bursts and the meiospores are liberated in the surrounding water. After swimming for some time these meiospores come to rest. They retract their flagella, enlarge and form the thick walled angular cells called polyhedrons or polyeders (Fig. 4 G, H). This stage is known as polyhedron stage.
Does Oscillatoria fix nitrogen?
In the sea, turbulence from wave action apparently separates trichomes allowing O2 to enter thus decreasing nitrogenase activity. These observations explain how Oscillatoria is able to fix N2 without heterocysts in an aerobic environment and why its blooms virtually always occur in calm seas.