Another primitive characteristic of sponges is the option of sexual or asexual reproduction. Budding and fragmentation allows Grantia sponges to form identical offspring while sexual reproduction permits genetic mixing. Environmental conditions including water temperature, tidal stage, and the phase of the moon need to be near perfect or else sexual reproduction by these sponges is postponed.
Cynthia D. Kelly , Thomas J. Fellers and Michael W. Visit the Molecular Expressions Website. Photo Gallery. Silicon Zoo. The spicules of Grantia have three prongs. What structures does Grantia have to get rid of waste? Since sponges are sedentary and cannot move around, these folded walls give them more surface area to absorb the nutrients and oxygen as they flow in.
Is Grantia Asconoid Syconoid or Leuconoid? Asconoid, syconoid, and leuconoid body forms are found in class Calcarea. Sycpha Grantia is a vase-shaped syconoid sponge that can live in colonies. Class Demospongiae is the largest class of sponges, usually brilliantly colored with monaxonal or tetraxonal siliceous spicules, sometimes bound together by spongin.
The syconoid canal system is therefore more efficient than the asconoid type and the leuconoid type is the most efficient.
As diploblasts, sponges including Grantia exhibit only two germ layers, the endoderm and ectoderm. Budding and fragmentation allows Grantia sponges to form identical offspring while sexual reproduction permits genetic mixing.
Besides supporting sponge cells, spicules can help larvae stay buoyant while in the plankton or reach the bottom at settlement, enhance reproduction success, or catch prey. The spongocoel is lined by a variety of cell types, each having a unique function: porocytes — line the pores of the sponge and are the structure through which water is taken into the organism.
The approximately 5, living sponge species are classified in the phylum Porifera, which is composed of three distinct groups, the Hexactinellida glass sponges , the Demospongia, and the Calcarea calcareous sponges. Sponges are characterized by the possession of a feeding system unique among animals.
Grantia demonstrates the sycon body plan in which the wall of the colony is folded into a series of internal and external canals that circulate water to bring in dissolved oxygen and prey while removing waste products. They interlock to provide support like the bones in familiar animals. Leuconoid sponges are the best adapted to increase sponge size. This body plan provides more circulation to deliver more oxygen and nutrients per area in large sponges.
Syconoid Canal System. Leuconoid Canal System. Sponges may reproduce sexually and asexually. After fertilization in the sponge, a larva is released into the water. It floats around for a few days and then sticks to a solid to begin its growth into an adult sponge. Sponges are also able to reproduce asexually through budding. Sponges use direct diffusion to exchange gases. The gases diffuse through the surface of the sponge.
Once inside, they diffuse to individual cells. Waste products are expelled through the osculum by the current created by the choanocytes to pull water into the sponge. How do sponges get their nutrition? Sponges are filter feeders and retrieve their nutrition from filtering the water that enters their pores and exits their osculum.
The food is captured by choanocytes and also amoebocytes who can digest it. Amoebocytes can also digest the food and carry nutrients to other cells.
As the water is moved along by the flagella, suspended food particles are drawn through the collar and then digested through phagocytosis by amebocytes. The amoebocytes carry nutrition to other parts of the sponge colony and compensate for the lack of a circulatory system.
There are about to 10, of species of Porifera that are known today. Out of them only species live in fresh water. The rest of the sponges dwell in salt-water. Large spicules that are visible to the naked eye are referred to as megascleres, while smaller, microscopic ones are termed microscleres. What are the two basic types of sponges? The two basic types of sponges are: encrusting or free-standing.
However, these are not part of the true classification of sponges it just makes it easier for us to categorize them. Encrusting sponges are similar to moss because they tend to cover the surfaces of rocks.
What are the three types of spicules? Based on the number of axis present in the rays spicules may be of three types: monoaxon, triaxon and polyaxon. Monaxon: These spicules grow along a single axis.
These may be straight needle-like or rod-like or may be curved. Their ends may be pointed, knobbed or hooked. What is the common name of sycon? Sycon ciliatum. Sycon ciliatum is a species of calcareous sponge belonging to the family Sycettidae. What structure is used to identify the three major classes of sponges?
Body types: Sponges have three body types: asconoid, syconoid, and leuconoid. Asconoid sponges are tubular with a central shaft called the spongocoel.
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