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What do sponges and cnidarians have in common?

What do sponges and cnidarians have in common?

Sponges have multiple cell types that are geared toward executing various metabolic functions. Cnidarians have outer and inner tissue layers sandwiching a noncellular mesoglea. Cnidarians possess a well-formed digestive system and carry out extracellular digestion.

How do sponges and cnidarians differ from flatworms and roundworms?

Porifera (sponges) have specialized cells and an endoskeleton but lack true tissues and body symmetry. Platyhelminthes (flatworms) have a mesoderm cell layer, simple organ systems, cephalization, and bilateral symmetry. Nematoda (roundworms) have a pseudocoelom and hydrostatic skeleton.

What is the main difference between sponges Porifera and cnidaria?

Cnidaria and porifera are two different phyla. Cnidarians have Cnidocytes but not the poriferans. Cnidarians have well-organized organ systems but not the poriferans; on the other hand, poriferans have an efficient tunnel system made up of pores but not the cnidarians.

What evolutionary advances do cnidarians have over the sponges?

The major evolutionary step that occurred with the phylum cnidaria was the development of tissue-level organization. Recall that sponges exhibit cellular-level organization but have no true tissues. A tissue is an aggregation of similar cells that work together to carry out a specific function within the body.

Do sponges have polyps?

It slowly increases its size by producing new, genetically identical polyps from adult polyps in a process called budding or through division of formed polyps. Division and budding are types of asexual reproduction. Sponges produce both types of reproductive cells, but usually release only sperm cells.

Why are sponges not considered Eumetazoans?

Terms in this set (93) sponge bodies different from the bodies of eumetazoans?) They have no true tissues or bilateral symmetry.

How do sponges survive without a nervous system?

Sponges are among the most primitive of all animals. They are immobile, and live by filtering detritus from the water. They have no brains or, for that matter, any neurons, organs or even tissues.

What is the difference between coral sponges and sea sponges?

While sponges, like corals, are immobile aquatic invertebrates, they are otherwise completely different organisms with distinct anatomy, feeding methods, and reproductive processes. The main differences are: Corals are complex, many-celled organisms. Sponges are very simple creatures with no tissues.

How do polyps differ from Medusas?

Polyp have a tubular shape and are fixed at their base, with the mouth present at the other end of the tube facing the water. Medusa have a bell shape, with tentacles hanging down. Polyp do not have a manubrium.

How are sponges and cnidarians similar to each other?

Sponges are similar to what might have been the ancestor of animals: colonial, flagellated protists. The cnidarians, or the jellyfish and their kin, are the simplest animal group that displays true tissues, although they possess only two tissue layers.

Why do sponges need to be in contact with water?

Sponges live in intimate contact with water, which plays a role in their feeding, gas exchange, and excretion. Much of the body structure of the sponge is dedicated to moving water through the body so it can filter out food, absorb dissolved oxygen, and eliminate wastes.

How are nutrients delivered to the sponge by choanocytes?

Food particles are trapped in mucus produced by the sieve-like collar of the choanocytes and are ingested by phagocytosis. This process is called intracellular digestion. Amoebocytes take up nutrients repackaged in food vacuoles of the choanocytes and deliver them to other cells within the sponge.

Why are sponges lacking a true digestive system?

Lacking a true digestive system, sponges depend on the intracellular digestive processes of their choanocytes for their energy intake. The limit of this type of digestion is that food particles must be smaller than individual cells. Gas exchange, circulation, and excretion occur by diffusion between cells and the water.