What is the main characteristic that separates annelids from other worms?
What is the main characteristic that separates annelids from other worms? Which segmented worm looks like a flower on a coral reef? Earthworms exchange carbon dioxide through the walls of a complex respiratory tube system inside their bodies. Annelids and flatworms share the trait of bilateral symmetry.
How are annelids different from other worms?
Annelids are segmented worms whereas roundworms are not segmented. Further, annelids have a true coelom while roundworms have a pseudocoelom. This means annelids have a well-developed mesoderm while roundworms lack a mesoderm. These are the main features that distinguish annelids from roundworms.
What worms are annelids other than earthworms?
Segmented worms are in the phylum Annelida, which has over 22,000 known species. These worms are known as the segmented worms because their bodies are segmented, or separated into repeating units. Besides the earthworm, the segmented worms also include leeches and some marine worms.
What separates annelids from arthropods?
A distinguishing characteristic shared by annelids and arthropods is their body segmentation. At some point in development, segmented animals possess a body plan with repeating segments of identical or similar structures. Later in development, some segments may form more specialized structures.
Is a spider an annelid?
The Annelid phylum contains three classes of organisms: Polychaeta, Oligochaeta and Hirudinea. The Arthropoda phylum contains five classes: Crustacea (shrimp and lobster), Arachnida (spiders and scorpions), Chilopoda (centipedes), Diplopoda (millipedes) and Insecta (roaches and beetles).
Is a spider a mollusk?
Spiders are arthropods and octopi are a late branch of molluscs. The last common ancestor of cephalopods and vertebrates existed more than 500 million years ago. So, the common ancestor of arthopods split with molluscs way before spiders and octopi ever existed.
Are jellyfish arthropods?
Since about 75% of all animal species are arthropods, they represent the largest invertebrate group. Cnidarians are also simple aquatic animals like sponges, but their possession of a nerve system makes them more complex than sponges. Jellyfish, hydras, sea anemones, and corals make up the four classes of cnidarians.
Do earthworms have chitin?
Chitin is a complex macromolecule, AKA a polymer. Chitin can be found in crustaceans, such as crabs, lobsters, and shrimp. It can also be found in insects, worms, fungus (or is it fungi?) and mushrooms….Chitin.
Are earthworms exoskeleton?
Earthworms are fairly simple life forms. Earthworms do not have an internal skeleton as we do, and they do not have a protective hard exoskeleton as does an insect. They are flexible, long bundles of muscle, especially designed for life underground.