Table of Contents
Are clams Protostome or Deuterostome?
Animals in the phylum Mollusca include clams, snails, octopuses, and sea slugs (pictured right). They are all protostome coelomates. Mollusks are characterized by their soft bodies, which are usually protected by a hard calcium carbonate shell.
Are clams a protostome?
Protostomia, group of animals—including the arthropods (e.g., insects, crabs), mollusks (clams, snails), annelid worms, and some other groups—classified together largely on the basis of embryological development.
Do bivalves have Cephalization?
For example, bivalves are not particularly cephalized (although some scientists have argued that they are “all head”). However, as with the echinoderms, certain mollusks regained cephalization. Their sense organs, including well-developed eyes and a brain, are concentrated in a distinct head region.
Are roundworms deuterostomes?
Flatworms, roundworms, mollusks, and annelids are all protostomes. As you learned in the Invertebrates concepts, these are the major features that distinguish protostomes from deuterostomes: The orientation of the first embryonic cell divisions.
Are cephalopods deuterostomes?
Octopuses are protostomes. All bilaterally symmetrical animals are divided into two groups: protostomes and deuterostomes. Early in development, a dent or depression called a blastopore forms in the embryo. In deuterostomes, which includes all vertebrates, this dent eventually forms into the anus.
Are chordates protostomes or deuterostomes?
All chordates are deuterostomes possessing a notochord. Animals in the phylum Chordata share four key features that appear at some stage during their development: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail (Figure 2).
Why are bivalves called bivalves?
A bivalve is an animal belonging to the class Bivalvia. Its name is a reference to the two shells, called valves, that protect its soft inner body parts. Bivalves like clams, oysters, scallops and mussels are commonly used throughout the world as a source of food for both humans and other animals.
Are adult bivalves sessile?
They are called bivalves because their shell is composed of two parts that are called valves. Is there digestive tract complete or incomplete? Clams have rounder and lighter shells, while mussels have darker shells. Adults are usually sessile, but the larva or _____ is free-swimming.
Are bivalves invertebrates?
Bivalves belong to the invertebrate phylum Mollusca, which also includes snails, squids, and octopuses. Some well-known bivalves include clams, scallops, mussels, and oysters. More than 15,000 species of bivalves exist. All bivalves are aquatic, encompassing both marine and fresh-water species.
Is a mollusk a Protostome or Deuterostome?
These phyla are divided into two groups based on their pattern of embryonic development: the protostomes and the deuterostomes. Flatworms, roundworms, mollusks, and annelids are all protostomes.
Is a cnidaria a Protostome or deuterostome?
Cnidaria are neither protostomes or deuterostome, as both of these superphylum belong to the Bilateria clade of animals, animals that exhibit…