What is the difference between invertebrate chordates and vertebrate chordates

What are Vertebrates — Definition, Classification, Characteristics 3. Chordates refer to an animal phylum that contains a notochord, dorsal central nervous system, pharyngeal gill slits, and a post-anal tail.

Chordates are classified into three subphyla: Urochordata, Cephalochordata, and Vertebra. Urochordata contains sea squirts and salps that secrete a tunica to the outside of the body.

Cephalochordata contains lancelets. Vertebrata contains mammals, birds, reptiles, amphibians, and fish. The diversity of chordates is shown in figure 1. Chordates are deuterostomes with a bilateral body plan. They are also coelomates. The notochord of chordates is a stiff, cartilage rod, which extends along the body. The dorsal nerve tube connects with the peripheral nervous system and acts as the central nervous system.

The pharyngeal gill slits occur just behind the mouth. They serve as a filter-feeding system in some chordates. The post-anal tail is a muscular tail and extends behind the anus.

Vertebrates refer to a large group of animals which consist of a backbone, surrounding the nerve cord. The central nervous system of vertebrates develops a brain, which is lodged in a brain case called the skull. Vertebrates also contain a notochord on the dorsal side of the gut.

Privacy Policy. Skip to main content. Search for:. Characteristics of Chordata Animals in the phylum Chordata share four key features: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

Learning Objectives Identify the key features of the chordates. Key Takeaways Key Points These characteristics are only present during embryonic development in some chordates. The notochord provides skeletal support, gives the phylum its name, and develops into the vertebral column in vertebrates.

The dorsal hollow nerve cord develops into the central nervous system: the brain and spine. Pharyngeal slits are openings in the pharynx that develop into gill arches in bony fish and into the jaw and inner ear in terrestrial animals.

The post-anal tail is a skeletal extension of the posterior end of the body, being absent in humans and apes, although present during embryonic development. Key Terms notochord : a flexible rodlike structure that forms the main support of the body in the lowest chordates; a primitive spine nerve cord : a dorsal tubular cord of nervous tissue above the notochord of a chordate pharyngeal slit : filter-feeding organs found in non-vertebrate chordates lancelets and tunicates and hemichordates living in aquatic environments.

Chordates and the Evolution of Vertebrates Chordata contains two subphylums of invertebrates: Urochordata tunicates and Cephalochordata lancelets. Learning Objectives Describe the features and phylogenetic history of lancelets and urochordata. Key Takeaways Key Points Urochordata tunicates and Cephalochordata lancelets are invertebrates because they lack a backone.

Larval tunicates Urochordata posses all four structures that classify chordates, but adult tunicates retain only pharyngeal slits. Larval tunicates swim for a few days after hatching, then attach to a marine surface and undergo metamorphosis into the sessile adult form.

Lancelets Cephalochordata are marine organisms that possess all features of chordates; they are named Cephalochordata because the notochord extends into the head. Lancelets may be the closest-living relatives to vertebrates.

The Evolution of Craniata and Vertebrata Both genomic and fossil evidence suggests that vertebrates evolved from craniates, which evolved from invertebrate chordates. Learning Objectives Explain how genomics informs scientists about chordate evolution. Key Takeaways Key Points The clade Craniata includes animals that have a cranium: a bony, cartilaginous, or fibrous structure that surrounds the brain, jaw, and facial bones.

Members of Craniata include the vertebrates and hagfish. Genomic evidence suggests that vertebrates diverged from cephalochordates lancelets , which had previously diverged from urochordates tunicates. Fossil evidence suggests that most vertebrate diversity originated in the Cambrian explosion million years ago. Two whole- genome duplications occurred in early vertebrate history. Key Terms cranium : the part of the skull enclosing the brain, the braincase genomics : the study of the complete genome of an organism Cambrian explosion : the relatively rapid appearance over a period of many millions of years , around million years ago, of most major animal phyla as demonstrated in the fossil record.

Characteristics of Vertebrates Vertebrata is a subphlyum of Chordata that is further defined by their bony backbone. Learning Objectives Identify the defining characteristics of vertebrates. Key Takeaways Key Points As chordates, vertebrates have the same common features: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. Vertebrates are further differentiated from chordates by their vertebral column, which forms when their notochord develops into the column of bony vertebrae separated by discs.

Vertebrates are the only chordates that have a brain as part of their central nervous system. Key Terms vertebral column : the series of vertebrae that protect the spinal cord; the spinal column chordate : a member of the phylum Chordata; numerous animals having a notochord at some stage of their development; in vertebrates this develops into the spine notochord : a flexible rodlike structure that forms the main support of the body in the lowest chordates; a primitive spine.

Licenses and Attributions. What is the difference between invertebrate chordates and vertebrate chordates? How are vertebrates different from invertebrates? Are the chordates and the vertebrates same or different? Can chordates reproduce asexually?

Why are fish chordates? Do all chordates have eyes? Do Lancelets only live in saltwater? Do Lancelets have eyes? Although insignificant and little known, these marine animals are of great scientific interest as it is generally accepted that their ancestors were close relatives of the ancestral vertebrate. Similarities between the chordates and living hemichordates suggest that they all evolved from a common ancestor belonging to the Class Graptolita, an extinct group of hemichordates.

The reasons for thinking this are:.