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Reef Zoo benthos
which is then gradually digested by the sponge cells. The 3H-label of alanine
appeared first in the bacterial cells and only later in the cells of the sponge
(Wilkinson and Garrone 1980). Other sources of feeding and biomass
production by these symbiotic bacteria are the waste products, excreted by
the sponge's tissues. The bacteria which live in the mesoglea consume also
the collagen material and the particulated matter which penetrate into the
mesoglea. Besides the production of biomass ultimately used by the sponge,
these bacteria also accomplish an important function in cleaning the
channels and the mesoglea, when an excess of old collagen filament and
particulate matter had been consumed. Thus they support a normal filtering
activity in the host sponge. Symbiotic heterotrophic bacteria are definitely
found in the following common reef sponges: Pericharax, Jaspis, Neofibularia, Casterospongia. The presence of symbiotic bacteria was recorded
even in eggs of some sponges. So these bacteria could be inherited through
generations (Levi and Levi 1976). In some sponges the symbiotic heterotrophic bacteria are present together with the blue-green algae.
The blue-green algae are known as symbionts only in sponges and in
some echiurid worms (Kawaguti 1971). They were first discovered in the
cells of sponges by Feldmann in 1933. Later, besides the blue-greens also
zooxanthellae and even a cryptomonad were found in them (Sara and
Liaci 1964). Most of the symbiotic sponges harbor a small unicellular
cyanobacterium Aphanocapsa feldmanni (or, more rarely, A. raspaigelea).
They are the specialized symbiotic species relative to pelagic Synechococcus.
Some sponges harbor the unicellular cyanobacteria Stephanocapsa feldmanni
and Synechocystic trididemnii as symbionts (Larcum and Cox 1988). Several
species of sponges (Tethya, Ulosa) contain filamentous chain species of the
cyanobacterium Phormidium spongeliae. These algal symbionts could be
found in approximately half of sponge species inhabitins the euphotic zone
of a reef (Vacelet 1981; Wilkinson and Trott 1985). The sponge Dysidea
harbors as symbiont the filamentous cyanobacterium Oscillatoria spongelina
(Borowitzka et al. 1988). The symbiotic cyanobacteria are usually accumulating about 1 cm deep in the illuminated upper layer of the sponge's body,
depending on the degree of light penetration into it. The unicellular symbionts are harbored by the sponge mostly inside the specialized cellscyanocycles in quantities up to several hundred per cell (Wilkinson 1980).
Some portion of them is present also in the mesoglea. The biomass of
symbiotic blue-green algae attains in some sponges up to 50% of their
cellular biomass. The multicellular filamentous cyanobacteria are located
mostly in the mesoglea. Cyanocytes control the multiplication of symbiotic
cyanobacteria inside them, as well as their metabolic rates, the same as the
cells of the coral polyp's ectoderm control those in the ir zooxanthellae.
They may stimulate the translocation of photosynthates by algal cells, thus
receiving from them the food by the biotrophical way. Another portion they
get of it by digesting the excess of the algal cell produced via the
phagotrophic mechanism (Sara 1971; Vacelet 1971). The translocation was
Reef Zoo benthos
which is then gradually digested by the sponge cells. The 3H-label of alanine
appeared first in the bacterial cells and only later in the cells of the sponge
(Wilkinson and Garrone 1980). Other sources of feeding and biomass
production by these symbiotic bacteria are the waste products, excreted by
the sponge's tissues. The bacteria which live in the mesoglea consume also
the collagen material and the particulated matter which penetrate into the
mesoglea. Besides the production of biomass ultimately used by the sponge,
these bacteria also accomplish an important function in cleaning the
channels and the mesoglea, when an excess of old collagen filament and
particulate matter had been consumed. Thus they support a normal filtering
activity in the host sponge. Symbiotic heterotrophic bacteria are definitely
found in the following common reef sponges: Pericharax, Jaspis, Neofibularia, Casterospongia. The presence of symbiotic bacteria was recorded
even in eggs of some sponges. So these bacteria could be inherited through
generations (Levi and Levi 1976). In some sponges the symbiotic heterotrophic bacteria are present together with the blue-green algae.
The blue-green algae are known as symbionts only in sponges and in
some echiurid worms (Kawaguti 1971). They were first discovered in the
cells of sponges by Feldmann in 1933. Later, besides the blue-greens also
zooxanthellae and even a cryptomonad were found in them (Sara and
Liaci 1964). Most of the symbiotic sponges harbor a small unicellular
cyanobacterium Aphanocapsa feldmanni (or, more rarely, A. raspaigelea).
They are the specialized symbiotic species relative to pelagic Synechococcus.
Some sponges harbor the unicellular cyanobacteria Stephanocapsa feldmanni
and Synechocystic trididemnii as symbionts (Larcum and Cox 1988). Several
species of sponges (Tethya, Ulosa) contain filamentous chain species of the
cyanobacterium Phormidium spongeliae. These algal symbionts could be
found in approximately half of sponge species inhabitins the euphotic zone
of a reef (Vacelet 1981; Wilkinson and Trott 1985). The sponge Dysidea
harbors as symbiont the filamentous cyanobacterium Oscillatoria spongelina
(Borowitzka et al. 1988). The symbiotic cyanobacteria are usually accumulating about 1 cm deep in the illuminated upper layer of the sponge's body,
depending on the degree of light penetration into it. The unicellular symbionts are harbored by the sponge mostly inside the specialized cellscyanocycles in quantities up to several hundred per cell (Wilkinson 1980).
Some portion of them is present also in the mesoglea. The biomass of
symbiotic blue-green algae attains in some sponges up to 50% of their
cellular biomass. The multicellular filamentous cyanobacteria are located
mostly in the mesoglea. Cyanocytes control the multiplication of symbiotic
cyanobacteria inside them, as well as their metabolic rates, the same as the
cells of the coral polyp's ectoderm control those in the ir zooxanthellae.
They may stimulate the translocation of photosynthates by algal cells, thus
receiving from them the food by the biotrophical way. Another portion they
get of it by digesting the excess of the algal cell produced via the
phagotrophic mechanism (Sara 1971; Vacelet 1971). The translocation was