Echinoderms are marine animals with radial symmetry. Some types of echinoderms are sea stars, sea urchins, sand dollars, and sea cucumbers.

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Is a hydra an echinoderm?

Echinoderms are characterized by radial symmetry, several arms (5 or more, mostly grouped 2 left - 1 middle - 2 right) radiating from a central body (= pentamerous). The body actually consists of five equal segments, each containing a duplicate set of various internal organs. They have no heart, brain, nor eyes, but some brittle stars seem to have light sensitive parts on their arms. Their mouth is situated on the underside and their anus on top (except feather stars, sea cucumbers and some urchins).

Echinoderms have tentacle-like structures called tube feet with suction pads situated at their extremities. These tube feet are hydraulically controlled by a remarkable vascular system. This system supplies water through canals of small muscular tubes to the tube feet (= ambulacral feet). As the tube feet press against a moving object, water is withdrawn from them, resulting in a suction effect. When water returns to the canals, suction is released. The resulting locomotion is generally very slow.

therefore, no. hydra supposedly had heart, brain and eyes and also do not have tentacles.
No, it's a Cnidarian

What distinctive features do all modern echinoderms share?

They are radially symmetrical, there is no cephalization ( no heads ) and they are, like you deuterostomes. ( indeterminate cleavage and a mouth that does not arise from the blasophore ).

Also, they are all marine animals and they have spiny skin.

Are Echinoderms habitat aquatic or land?

In my personal opinion, they could be either.

But, in my professional opinion, Echinoderms habitat would have to be neither; because they are a type of germ (it would have to be air).

Which feature would you find on an echinoderm?

novanet: an endoskeleton you cheaters get back to work

What happens to echinoderm larvae when they metamorphose into adults?

Echinoderms have swimming larvae that are bilaterally symmetrical, with left and right sides, but they do not 'develop into' bottom-living adult echinoderms, which are radially symmetrical, often star-shaped. The juvenile (young adult), radial from the start, grows from a group of stem cells within the larva. It gradually moves to the outside of the larva, and the larva and juvenile develop side-by-side. In most cases, the larva eventually settles and shrivels, and the juvenile crawls away. In one species of starfish, however, the juvenile drops off the swimming larva, which can go on swimming for a further three months.

Are sponges echinoderms?

No. Sponges belong to the phylum Porifera, which means 'pore bearing.' The have pores that are called incurrent vents, where water comes in, and excurrent vents, where water goes out. They are considered the most primitive of animals because they don't have any complex organs or tissues, so, for example, they don't have a circulatory system or a digestive system or a nervous system. Their cells are somewhat loosely structured in that some cells can move around from place to place in the sponge and there are some unspecialized cells that can become other kinds of cells. Also, they only have two layers of cells. There are some types of sponges that you can put through a sieve to separate all the cells but then the cells will go back together to recreate a sponge again.

Echinoderms are a completely different and more advanced phylum. They have organ systems and fixed (non-changing) cell types and more layers of cells. Also, if you put an echinoderm through a sieve, he's a gonner.

What adaptations have echinoderms developed to survive?

echinoderms only come out in the dark so other animals don't see them.

How can echinoderms survive without a head?

Echinoderms have all the same organs as are normally found concentrated in the head only they have them scattered. So what if their eyes are on their legs if they still see. It is the seeing that is important, not the location of the eyes.

What are the examples of echinoderms?

There are over 6000 types of echinoderms. A few examples are the banded-arm brittle star, common sea urchin, cushion sea star, etc. I you were looking for types of echinoderms, they are

  • Sea star or starfish (Asteroidea)
  • Brittle stars, basket stars, serpent stars (Ophiuroidea)
  • Sea urchins, heart urchins and sand dollars (Echinoidea)
  • Holothurians or sea cucumbers (Holothuroidea)
  • Feather stars and sea lilies (Crinoidea).

What is an echinoderm?

An echinoderm is a sea animal that has a hard spiny shell, or exoskeleton. Echinoderms display radial symmetry, having 5 similar body extensions from a central point.

The seven classes of echinoderms are brittle stars, basket stars, sea urchins, sand dollars, sea lilies, feather stars, and sea cucumbers.

In echinoderms could fertilization take place without water?

No because the sperm and egg cells have to be released into the water where the eggs are usually fertilized. :) ☆彡 NEON STAR

What is an example of an echinoderm?

Sea star, sea urchin and also sea cucumbers.

What are echinoderms eating habits or diet?

Echinoderms eat a variety of sea life. Depending on the type of echinoderm dictates its diet. Many eat snails, sea urchins, barnacles, mussels and clams. They use their feet to suck open a shell such as a clam, and then put their stomachs over the opening to suck out their meal.(:

Glad i Could Help .

How do echinoderms reproduce?

They reproduce asexually and sexually. After the female releases her eggs the male lets out a sperm which fertilizes the eggs.

Asexually probably by budding!

A few species provide some nurturing of the young.