What does the mouth of the cnidarian open into? The mouth opens into the gastrovascular cavity.
In this regard, what does the movement of water through a sponge provide?
The movement of water through the sponge provides a simple mechanism for feeding, respiration, circulation, and excretion.
Keeping this in consideration, why is it advantageous to have sensory cells encircling the bell of the Medusa?
Why is it advantageous to have sensory cells encircling the bell of the medusa? It allows the animal to sense predators and prey. … Flatworms lack organs specialized for gas exchange and circulation, and most nitrogenous waste diffuses directly out of the cells into the surrounding water.
Is Hydra a polyp or medusa?
Hydra exists in both forms: Polyp and Medusa. These forms are dependent upon nutritional content of the living environment. Medusa is the adult and sexual form whereas Polyp is juvenile and asexual form. Under harsh living conditions and starvation, hydra reproduces sexually.
How do sponges meet their need for energy?
But sponges are animals because they must take in food, and they are multicellular. All animals need food, water, and oxygen to survive. Sponges get food by straining the water that comes through their pores. Oxygen is also obtained from the water the sponge lives in.
How do sponges defend themselves?
The pointed sponge spicules function as one method of defense against predators. Sponges also defend themselves by producing chemically active compounds. Some of these compounds are antibiotics that prevent pathogenic bacterial infections, and others are toxins that are poisonous to predators that consume the sponge.
Are our bodies full of pores?
Phylum porifera are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.
What type of symmetry do sponges have?
Asymmetry. Only members of the phylum Porifera (sponges) have no body plan symmetry. There are some fish species, such as flounder, that lack symmetry as adults. However, the larval fish are bilaterally symmetrical.
What kind of fertilization do sponges use?
Most sponges are hermaphrodites, meaning they produce both eggs and sperm. Since eggs and sperm are produced at different times, self-fertilization is avoided. In most species of sponges, sperm cells from one sponge enter another sponge through its pores, as shown in Figure 5.
What are the feeding habits of sponges?
Diet: Sponges are filter feeders. Most sponges eat tiny, floating organic particles and plankton that they filter from the water the flows through their body. Food is collected in specialized cells called choanocytes and brought to other cells by amoebocytes.
What are the three classes of sponges?
Sponges were traditionally distributed in three classes: calcareous sponges (Calcarea), glass sponges (Hexactinellida) and demosponges (Demospongiae).
What is the larva of a sponge called?
After reproduction, sponge produces larva called as stomoblastula. It has a mouth and feeds on nurse cells within mesogloea and grows for a few days. Stomoblastula develops into an amphiblastula by inverting inside out and brings the flagellated cells on the outer surface, so that the larva can swim in water.
What is a Spicule?
1 : a slender pointed usually hard body especially : one of the minute calcareous or siliceous bodies that support the tissue of various invertebrates (such as sponges) 2 : a spikelike short-lived prominence appearing close to the chromosphere of the solar atmosphere.
