Why are echinoderms more closely related to chordates than other phyla?
Echinoderms and Chordates are more closely related to each other than they are to other animals because the coelom ( an open fluid-filled body cavity lined with tissues) found in the animals of this phylum is made from the digestive tube & the endoskeleton present in the body are composed of 95% of calcium carbonate …
Why are echinoderms considered to be closely related to chordates answers com?
Echinoderms are closer to Chordates than any other phylum: During embryonic development, the first aperture that is formed in deuterostomes is a primitive anus.
Do squids have a closed circulatory system?
The larger more complex crustaceans, including lobsters, have developed arterial-like vessels to push blood through their bodies, and the most active mollusks, such as squids, have evolved a closed circulatory system and are able to move rapidly to catch prey.
Why do giant squids have blue blood?
More primitive species (like the octopus, squid, and a number of other invertebrates) use a different protein, called hemocyanin, which relies on copper, rather than iron, as the binding mineral of choice. When copper binds with oxygen, the discoloration is different, resulting in the blue color of their blood.
Why are squid hearts white?
The gill hearts can be hard to locate. Female squid also have a Nidamental gland. This is a large white organ, which sits on top of the other internal organs and is used in coating the eggs before they are released into the water. This can be removed gently to expose the other organs when carrying out the dissection.
Why do squids have 3 hearts?
The branchial hearts pump blood to the gills, where oxygen is taken up. Blood then flows to the systemic heart, where it is pumped to the rest of the body. The systemic heart is made of three chambers: a lower ventricle and two upper auricles.