what is water canal system
Answers
Answer:
water canel system that use to support farmers by giving them water to farm
CANAL SYSTEM IN SPONGES
Body of all sponges is the perforated by large number of apertures through which water enters Inside body and flows through a system of criss-crossing canals collectively forming the canal system which is a characteristic feature of poriferans. Following types of canal systems are found in sponges:
Ascon type, with flagellated spongocoel
Sycon type, with flagellated radial canals
Leucon type, with flagellated chambers
Rhagon type, with conical shape and broad base
ASCON TYPE
This is the simplest type of canal system and is found in Leucosolenia and other homocoela. Ostia are present on the surface of body and lead directly into the spongocoel, which is lined by flagellated choanocyte cells. Spongocoel opens to the outside through a narrow circular opening, the osculum located at the distal free end of the sponge body. Water enters through ostia into spongocoel and goes out of body through the osculum.
SYCON TYPE
This type of canal system is a characteristic of syconoid sponges, e.g. Scypha and Grantia. Body wall is secondarily folded to form incurrent and radial canals, which open into the spongocoel by an opening called apopyle. Both types of canals are interconnected by minute pores called prosopyles. Incurrent pores or ostia are found on the outer surface of body and open into the incurrent canals, which lead into adjacent radial canals through minute openings called prospyles. Radial canals are the flagellated chambers that open into central spongocoel by internal openings called apopyles. Spongocoel is a narrow, without flagellated cells but is lined by pinacocytes and opens to exterior through the osculum.
In more complex sycon type, as found in Grantia, the incurrent canals travel along an irregular course through the tissue and connect to the radial canals, thus forming large sub-dermal spaces.