Echinoderms

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.

they are in the shape of a star

There are many places one can go to purchase starfish pendants. One can first visit their local jewelry stores or the jewelery counter at their local department store such as Sears. Online options would be Amazon or even eBay.

Starfish, or sea stars, play a crucial role in marine ecosystems, primarily as predators that help maintain the balance of species populations on coral reefs and in other habitats. By controlling the abundance of certain prey, such as mollusks, they contribute to the overall health of the ecosystem. However, in some cases, an overpopulation of certain starfish species, like the crown-of-thorns starfish, can lead to coral reef damage, indicating that their impact can be both beneficial and detrimental depending on the context. Overall, their presence is essential for ecological balance in their environments.

Echinoderms, such as starfish and sea urchins, typically inhabit marine environments, particularly in shallow waters along coastlines, coral reefs, and rocky substrates. They can also be found at various depths in the ocean, from tidal pools to deep-sea habitats. Their unique water vascular system allows them to navigate and thrive in diverse marine ecosystems.

In starfish, the cleavage is typically described as irregular or unequal, resulting in blastomeres of varying sizes. This is due to the specific patterns of division that produce larger and smaller cells rather than uniform-sized blastomeres. As a result, the early embryonic development of starfish reflects this uneven distribution in cell sizes, which is characteristic of their specific type of holoblastic cleavage.

their body plan

A clownfish protects itself by living inside poisonous sea anemone. It is unknown how it doesn't get stung. It is inferred that they have a layer of mucus that protects them from the stings.

Their skin is covered with bumpy gills.

• They have radial symmetry
• They have internal calcareous skeleton
• They are often covered with spines (sea urchins, etc)

Yes.

Imagine cutting a starfish or a sand-dollar in half.

It will be symmetrical on both sides, just like a mirror image.

Hope this helps!

:3

sea cucumber

ning

Sea urchins and sand dollars.

Echinoderms live only in the sea.

Echinoderms, a group that includes starfish, sea urchins, and sea cucumbers, exhibit a range of mobility. While many species, like sea stars, can move slowly using tube feet, others, such as sea cucumbers, can be more sedentary but are not completely sessile. Some echinoderms, like certain sea lilies, are largely attached to the substrate and display a sessile lifestyle. Overall, echinoderms can be both mobile and, to a lesser extent, sessile, depending on the species.

Echinoderms have a very spine-like outer structuring. Also, with their distinct colors they are easily classifiable. Thirdly, they seem mostly to be of a thin body structure.