A new group of echinoderms, the sea daisies, or concentricycloids, wasdiscovered in 1986. They are deep-water animals living on sunken wood.They are flat and round, looking very much like a small sea star withoutarms. They also lack a gut. Without ever having seen them, why do youthink they were classified as echinoderms, not as members of a new phylum? Do you have any hypotheses as to how they feed or move around?

Q: Flatworms have no coelom. Recent gene sequencing shows that their closest relatives are the rotifers…

A: Coelom is the fully functional body cavity that is lined by mesoderm. Within the coelomic cavity,…

Q: completely converted into the water-vascular system. restricted to a small space around the gonads.…

A: Echinoderms have a spacious coelom (an open, fluid-filled body cavity lined with tissue), large…

Q: Do echinoderms have respiratory and circulatory systems?

A: Echinoderms have a calcareous endoskeleton with organ-system organization. They are triploblastic…

Q: Please choose all that apply for Phylum Arthropoda. segmentation coelom hemocoel O endoskeleton O…

A: Introduction:- Animals without a notochord – the rod-like elastic structure that supports the body –…

Q: What type of body plan do echinoderms have? (MARK ALL THAT APPLY) Obilateral symmetry O pentaradial…

A: The phylum of invertebrates involving starfish, sea cucumbers, sand dollars, etc is called the…

Q: What evidence suggests that radial symmetry in echinoderms was secondarily derived?

A: Radial symmetry means that you cut an organism along any diagonal you will get two equal halves of…

Q: What are the reason that you can think of for the arthropods to constitute the largest group of…

A: Arthropods are the invertebrate animals that have a segmented body, paired jointed appendages, and…

Q: Explain how each molluscan feature is modified, compared to gastropod and bivalve body plans. 1)…

A: Cephalopods, Gastropods and Bivalvia are all classes of Molluscs. They differ in their habitats. For…

Q: Bivalves lack a mantle (True/False)?

A: The name bivalve refers to the limy shell. They are composed of two pieces or valves, right and left…

Q: clitellum is the: Hirudina Cestoda Oligochaeta Platyhelminthes Permoclitellata All lack a permanent…

A: Clitellum is a glandular and unsegmented region of earthworms. It is situated near the head region…

Q: illustrates four key characters ofchordates: a notochord; a dorsal, hollow nerve cord; pharyngeal…

A: A chordate is an animal of the phylum Chordata. During some period of their life cycle, chordates…

Q: SO you wish to be a chordate do you? Which of the following are not essential to that distinction? O…

A:

Q: Which statement best describes the symmetry of brachiopods compared to bivalves?     Both…

A: Brachiopods are organisms belonging to Phylum Brachiopoda and  bivalves belong to Phylum Mollusca,…

Q: Which of the following is not a characteristic of the phylum Chordata

A: The phylum Chordata is a group of animals that includes vertebrates (animals with backbones) as well…

Q: Echinodermata is the first phylum you have examined whose members possess true endoskeletons. What…

A: Echinodermata are called after their spiny skin, and so this phylum has over 7,000 recognized living…

Q: Which group of Chordata maintains the vertebrate characteristics throughout life? Cephalochordata…

A: Chondrichthyes are a group of fish that includes sharks, rays & chimeras. They are characterized…

Q: Why are echinoderms considered part of the Deuterostomes, despite having incredibly unique…

A: Echinoderms are marine, spiny invertebrates belonging to the phylum Echinodermata, superphylum…

Q: Which of the following are the defining features of animals that belong to the phylum chordata?…

A: Kingdom Animalia has some specific characteristics like motility, multicellularity, the requirement…

Q: Why are Echinodermata known as the sister group to the chordates?

A: Starfish, brittle stars, sea cucumbers, sea urchins, sand dollars, and crinoids are all members of…

Q: Imagine you come across a small worm. How can you determine whether it is a class Hirudinida or a…

A: Introduction :- Organisms are classified amongst various classes, orders , family according to their…

Animal Phylogeny

Cladistics is a method of biological classification where organisms are classified based on their ancestors and their relationship with them. It is defined as the concepts and methods for determining the branching patterns of evolution and evolutionary history. Some scientists, however, have preferred the term phylogenetic systematics or phylogenetic taxonomy to emphasize the reliance on a phylogeny for classification. It is the most common and accepted method for classifying organisms.