What is the type of digestive system present in beings of the phylum Arthropoda? Are these animals protostomes or deuterostomes?

Which of the following is the correct classification for the following invertebrate animal: This animal has a wedge shaped muscular "foot", and it is a filter feeder.  This animal is covered by two shells connected by hinge ligaments.   Question 22 options:   a)  Phylum Mollusca, Class Bivalvia   b)  Phylum Chordata   c)  Phylum Echinodermata   d)  Phylum Arthropoda, subphylum Hexapoda   e)  Phylum Platyhelminthes   f)  Phylum Echinodermata   g)  Phylum Annelida

Pharyngeal slits are which of the following?   Question 24 options:   a)  Openings in the pharynx.  In aquatic chordates they allow for exit of water that enters the mouth.   b)  Elongations of the posterior portion of the body.  Use for locomotion in fish, or balance in some terrestrial vertebrates.   c)  Flexible, rod-shaped structures that grows from mesoderm.  Gives support to an animal in embryonic development of chordates or for entire life depending on the species.   d)  Tissues that produces thyroid type hormones.   e)  Hollow tubes that develops from ectoderm.  Develops into the central nervous system.

Is the presence of myomeres a symplesiomorphic or synapomorphic feature of vertebrates compared to conditions in other deuterostome metazoans? And are these structures symplesiomorphic, synapomorphic, or neither for vertebrates considered alone?

Why are echinoderms considered part of the Deuterostomes, despite having incredibly unique morphology?

Define adaptation. How could you use a comparative approach to test whether mesoglea within a scyphozoan medusa was an adaptation for buoyancy? How could you use a different criterion to test whether the eyes of cubozoans were adaptive? Where would a comparative approach prove a better way to assess the adaptive values of a tegument in internal parasites: in tapeworms or nematodes? Why?

Create a body plan table (Insert → Add Table) for the following animal phyla: Porifera, Cnidaria, Platyhelminthes, Mollusca, Annelida, Nematoda, Arthropoda, Echinodermata, and Chordata. Describe each phylum by identifying the following body plan features.  1) Symmetry: Asymmetrical, Radial, or Bilateral 2) Tissue type: Parazoa, Eumetazoa (diploblastic), or Eumetazoa (triploblastic) 3) Body cavity (if triploblastic): Acoelomate, Psuedocoelomate, or Coelomate 4) Developmental mode (if Coelomate): Protostome or Dueuterostome Note: Depending on the body plan, features 3 & 4 may not apply to specific phyla. * Please answer 1) and 2) only. Reposting question for other two to be answered.

How do the presence/loss, form, and function of the radula differ within members of the Classes Bivalvia, Polyplacophora, and Cephalopoda (using the squid as a representative)? B) How does this relate to the animals’ natural histories?

Cnidarians and ctenophores are considered diploblastic, but why might some biologists label them triploblastic?

What does radial symmetry means? What is the type of symmetry found in chordates? Which are other phyla of the animal kingdom that present species with radial symmetry?