Since De Bary's proof of the germination of the zoospores and of the infection of the leaves, the course of the hyphae in them and in the haulms, the origin of the conidia, etc.
These zoospores are amoeboid; they soon secrete a shell and reveal themselves as megalospheres, the original state of the megalospheric forms.
These zoosporeson leaving the sea-weed in many respects resemble the lower orders of animal life, having, like the latter, the property of moving.
In most zoospores I could distinctly observe only a single long flagellum; sometimes, however, two or even three appeared to be present, but the determination of their number is very difficult.
Active free-swimming movements are only met with in the case of the flagellate zoospores (s 142).
The fate of the flagellate zoospores which emerge from the mature central capsule of the Radiolaria has not hitherto been decided by actual observation; all attempts to rear the swarming zoospores have been in vain, for they have soon died.
The size of the flagellatezoospores which emerge from the ruptured central capsule and swim freely in the water by means of their flagellum, varies generally between 0.
The walls of the cells either gradually degenerate, or are fractured, and the zoospores are thus set free.
The zoospores thrown off by the weeds, particularly in the autumn, are also valuable as food for some of the animals.
The processes are directed towards each other, and unite to form a tube in which the contents of the two cells become fused together, with the result that zoospores are produced.
Certain of the cells become modified into what are called zoosporangia, and the minute zoospores are formed within them.
From very similar spore cases a number of zoospores are liberated and for a time they swim about freely.
The formation of zoospores may be easily observed in the brown sea weed Ectocarpus Siliculosus we have already mentioned.
One of these swarming zoospores fuses with the individual which first ceased swimming about, with the result that a much larger, non-swimming individual is formed which, after a short resting period, germinates and grows into a new sea weed.
The remainder of the zoospores will come to rest later and germinate to form new plants just as though no fusion had taken place with two of their number.
Should we have this good fortune we must hasten to magnify more highly the zoospores which have escaped from the pear shaped spore case.
The formation of zoospores by green felt (Vaucheria) may occur only in darkness, at night, or in diffuse light, and these examples might be multiplied indefinitely.
Zoospores may be seen collected against the side of the vessel receiving direct sunlight, while the opposite side of the vessel will be free from them.
Locomotor movements are chiefly confined to lower forms, and are most noticeable in the "swarm spores," or zoospores of the algae, though exhibited by spermatozooids as well.
The movement is precisely that of the zoospores of Algæ.
In Peronospora, it has been demonstrated that certain species produce minutezoospores from the so-called spores.
Its ultimate development by production of zoospores is similar to the production of zoosporesfrom conidia, which it is unnecessary to repeat here.
In Achlya dioica the antheridium is cylindrical, the plasma which it encloses is divided into particles, which attain nearly the size of the zoospores of the same plant.
The zoospores being furnished with vibratile cilia, are for some time active, and need only water in which to disseminate themselves, and this is furnished by rain.
The generation of the zoospores commences within from an hour and a half to three hours after the sowing of the conidia on water.
The movement of the zoospores ceases at the end of from fifteen to thirty minutes.
It is true one may argue that the zoospores of certain cryptogamia exhibit similar movements; but do not these zoosporespossess as much of an animal nature as do the spermatozoa?
Zoospores arise in cells of ordinary size and form termed zoosporangia.
In these cases, however, the potential gametes may, failing conjugation, germinate directly, like the zoospores derived from unilocular sporangia.
The assertion of Areschoug that conjugation occurs among zoospores derived from unilocular sporangia, in the case of Dictyosiphon hippuroides, is no doubt to be ascribed to error of observation.
When zoospores come to rest, a new cell is formed and germination ensues at once.
Zoospores are of two kinds: (1) Those which come to rest and germinate to form a new plant; these are asexual and are zoospores proper.
In all other cases, zoospores are uninucleate bodies.
Aplanospores would seem to representzoospores arrested in their development; without reaching the stage of motility, they germinate within the sporangium.
Both aplanospores and akinetes may germinate with or without the formation of zoospores at the initial stage.
In coenocytic forms the zoospores would seem to arise simultaneously, probably because many nuclei are already present.
With regard to true reproduction, which is characterized by the formation of special cells, the group Euchlorophyceae is characterized by the production of zoospores (Gr.
But it is difficult to apply such a term at all to those cases in which there intervene between the oospore and the next sexual stage a series of generations, the zoospores of which are all precisely similar.
He has also seen Pleurococcus viridis dividing so as to form a filament, but has not succeeded in seeing the formation ofzoospores as described by Chodat.
Motile zoospores which escape from the zoosporangium are present except in Aplanes.
K, Germination of the zoospores formed in the sporangia.
Sexual reproduction by oogonia and antheridia; asexual reproduction by zoospores or conidia.
Mycelium poorly developed or absent; oogonia and antheridia (without antherozoids) known in some cases; zoospores common: Chytridiaceae.
On the other hand, the uniciliate zoospores of Polyphagus have slightly amoeboid movements, and in this and the pseudopodium-like nature of the protoplasmic processes, such forms suggest resemblances to the Myxomycetes.
Reproduced by zoosporesformed from the cell contents and breaking out from the surface, or by motionless spores formed from the whole contents.
Reproduction by zoospores formed of the whole contents of a cell, with a crown of numerous cilia; resting spores formed in sporangial cells after fecundation by ciliated spermatozoids formed in antheridial cells.
Fructification: zoospores produced from the cell contents of the filaments; resting spores formed from the contents of particular cells after impregnation by ciliated spermatozoids produced in distinct antheridial cells.
The families are formed either of assemblages of coated zoospores united in a definite form by the cohesion of their membranes, or assemblages of naked zoospores inclosed in a common investing membrane.
Microscopic cellular fresh water plants, composed of groups of bodies resembling zoospores connected into a definite form by their enveloping membranes.
Reproduced by division and by resting spores produced in sporangia formed after the conjugation of two cells and union of their contents, and by zoospores formed in the vegetative cells or in the germinating resting spores.
After a period of rest, the contents of the oospore break up into a number of zoospores like those already described, each of which, after a period of activity, germinates in the ordinary way.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "zoospores" in a variety of sentences. We hope that you will now be able to make sentences using this word.
