Life cycle of Ectocarpus siliculosus. Both Ectocarpus sexual and asexual life cycles are displayed. Gametes (right side) released from WT male gametophytes . The life history of Ectocarpus fasciculatus var. refractus (Kiitz.) Ardis. from Roscoff , France, has been studied in culture. This species proved to be the sporophytic. the sexual pheromones and infection of Ectocarpus by viruses. A proposition to (the life cycle can be completed in three months) and the ease with which.
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After some time they get free from the gelatinous mass and swim freely in water. The zoospores of plurilocular and unilocular sporangia cyycle identical in structure but zoospores of plurilocular sporangia are diploid and zoospores of unilocular sporangia are haploid. On the other hand, unilocular sporangium produces zoomeiospore through meiosis, followed by several mitotic divisions. The cells are arranged in vertical row Fig.
The unilocular sporangia develop singly on tips of small cyxle. Each unit then ectocsrpus into a single, uninucleate 2n and biflagellate zoospore. The diploid plants bear both unilocular and plurilocular sporangia.
Each zoospore is pyriform, uninucleate with two laterally inserted unequal flagella. The two gametes of same gametangium or from two different gametangium of same thallus fuse to from zygospore. The zoospores of plurilocular and unilocular sporangia are identical in structure but zoospores of plurilocular sporangia are diploid and zoospores of unilocular sporangia are haploid.
Life Cycle of Ectocarpus (With Diagram) | Algae
The terminal cell of the branchlet gradually increases in size and becomes ellipsoidal. Liberation of the swarmer is through a pore on the cell wall Fig. The active male gametes cluster around female gamete and cling themselves by their anterior flagellum. The zygospore germinates after days. The diploid plants bear both unilocular and plurilocular sporangia.
They named the plurilocular reproductive structures as neutral sporangia.
The sexual thalli of Ectocarpus are haploid. The isogametes or anisogametes fuse to form diploid zygospore. Reproductive Structures of Ectocarpus Algae.
Quick Notes on Ectocarpus (With Diagram) | Algae
The diploid nucleus of zygospore divides mitotically during germination. Reproductive Structures of Ectocarpus Algae.
In isogamous species the fusing gametes are morphologically and physiologically similar. These two types of zoosporangia may be produced on the same plant or on different plants. After sometime one male gamete fuses egg to lifs zygospore and other gametes detach themselves from female gamete.
Occurrence of Ectocarpus 3.
Life Cycle of Ectocarpus (With Diagram) | Phaeophyta
Some species of Ectocarpus are epiphytic e. It is known as clump formation. Fucosan vesicles or granules are present in large number along with pyrenoid like bodies in the cell.
The zoospores formed from plurilocular sporangia are alike with the zoospores i. The formation of unilocular and plurilocular sporangia is affected by environmental conditions like temperature and salinity of water.
This stage is called clump formation Fig. The protoplast of each cubical cell in gametangium metamorphosis into single biflagellate pyriform gamete. Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top.
The sexual reproduction may be isogamous, anisogamous or oogamous.
Ectocarpus: Occurrence, Features and Reproduction
Both sporangia and gametangia are occasionally found on the same plant. Then vertical divisions start in all the cells starting with the median cells of the row.
These zoospores are haploid, they withdraw flagella and attach to the substratum by ectocrapus anterior ends. The gametes are biflagellate, motile and are produced in plurilocular gametangia borne on haploid or unisexual plants.
The zygospore germinates after days. Answer Now and help others. No reduction division takes place during zoospore formation, hence all the zoospores are diploid.
Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top. These plants are called gametophytic plants as on maturity they bear plurilocular gametangia. In this article we will discuss about the life cycle of ectocarpus, explained with the help of suitable diagrams. The protoplast of each diploid uninucleate cell of the sporangium is transformed into a single biflagellate zoospore Fig.