What is a distinctive feature of the Chondrichthyans?

What is a distinctive feature of the Chondrichthyans?

Cartilage and teeth; many many teeth. Sharks, skates, rays and holocephalans belong to a group of fishes called the Chondrichthyes (=cartilaginous fishes). The most distinctive characteristic of chondrichthyans is their skeleton.

What do vertebrates and tunicates share?

The common characteristics between the tunicates and vertebrates are the presence of a notochord and a dorsal hollow nerve cord. Thus the correct answer is [e], a notochord and a dorsal hollow nerve cord.

Which of the following structures is are characteristic of vertebrates?

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.

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What is the term for those animals that have a notochord at some point in their life?

Members of this phylum are called chordates. Chordates share some common traits. At some point in their life cycle, they have a notochord, a nerve cord, and pharyngeal (fayr uhn JEE uhl) slits in the neck or throat. Lancelets are one chordate species that keep the notochord throughout their life cycle.

Why is amphioxus not a vertebrate?

Amphioxus also known as lancelet is a fish-like marine chordate. Unlike vertebrates, the dorsal nerve cord is not protected by bone but by a simpler notochord made up of a cylinder of cells that are closely packed to form a toughened rod.

What is notochord 11?

Answer Verified. Hint: -The notochord is a midline structure that is present in all the members of chordates. -It is the beginning of the formation of the backbone. -It is present from the head to the tail of the organism and in between the digestive tube and nerve cord.

What does notochord mean?

In anatomy, the notochord is a flexible rod formed of a material similar to cartilage. If a species has a notochord at any stage of its life cycle, it is, by definition, a chordate.

What is notochord function?

The notochord is an embryonic midline structure common to all members of the phylum Chordata, providing both mechanical and signaling cues to the developing embryo. Besides its primary structural function, the notochord is also a source of developmental signals that patterns surrounding tissues.

Which of the following is not a character of Chordata?

In some chrodats notochord is replaced by vertebral colum in adult stage. Protochordates i.e., Urochordates and Cephalochordates don’t have a well developed spinal cord. Thus, the correct answer is option D.

What are the 5 characteristics of chordates?

The five characteristic features of chordates present during some time of their life cycles are a notochord, a dorsal hollow tubular nerve cord, pharyngeal slits, endostyle/thyroid gland, and a post-anal tail.

What characteristics do Hemichordates share with chordates?

38. An important characteristic that Hemichordates share with Chordates is Absence of notochord Ventral tubular nerve cord Pharynx with gill slits Pharynx without gill slits

  • Absence of notochord.
  • Ventral tubular nerve cord.
  • Pharynx with gill slits.
  • Pharynx without gill slits.
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In which of the following notochord is absent?

In the sub-phylum (_i_) notochord is present only in the larval tail, while in (_ii_), it extends from head to tail region and is persistent throughout their life.

In which animal vertebral column is absent but notochord is present?

Notochord is present during the embryonic period only. After that, the notochord is replaced by a cartilaginous or bony vertebral column in the adult….VERTEBARATA.

Chordates Non-chordates
Heart is ventral. Heart is dorsal (if present).
Post anal tail is present. Post anal tail is absent.

What is the function of Atriopore in Urochordata?

The adult can then start filter feeding. It does this by sucking water into its mouth through a pharynx with slits that captures food and spitting the water back out a different opening called the atriopore.

In which of the following animals notochord does not persist throughout life?

The animals in which the ‘notochord’ is not present throughout the life are the urochordates like tunicates. Explanation: A notochord is a skeletal rod like structure that supports the entire body

What are chordates and non chordates?

The major point to differentiate between chordates and non-chordates is that chordates have a spinal cord or backbone in their body structure whereas non-chordates are without backbone or notochord in their body structure. …

Is the notochord hollow?

The characteristic features of Chordata are a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

In which group the members of the phylum Chordata belongs?

Phylum Chordata belongs to the Kingdom Animalia and includes all the vertebrates, i.e., animals with a backbone, and several invertebrates, i.e., organisms without a backbone. They possess a bilaterally symmetrical body and are divided into three different sub-phyla.

What are 3 main characteristics of the phylum Chordata?

Characteristic Features of Phylum Chordata

  • They are bilaterally symmetrical and triploblastic.
  • Chordates are coelomate and show an organ system level of organisation.
  • They have the characteristic notochord, dorsal nerve cord, pharyngeal slits.
  • Also, they have a post-anal.
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What classifies a Chordata?

A chordate (/ˈkɔːrdeɪt/) is an animal of the phylum Chordata (/kɔːrˈdeɪtə/). During some period of their life cycle, chordates possess a notochord, a dorsal nerve cord, pharyngeal slits, and a post-anal tail: these four anatomical features define this phylum.

What are the 5 classes of phylum Chordata?

The phylum chordata (animals with backbones) is divided into five common classes: fish, amphibians, reptiles, mammals and birds.

Which animals are chordates?

Chordates (Chordata) are a group of animals that includes vertebrates, tunicates, lancelets. Of these, the vertebrates—lampreys, mammals, birds, amphibians, reptiles, and fishes—are the most familiar and are the group to which humans belong

What are the 9 major phyla?

  • * Porifera (sponges)
  • * Cnidaria (jellyfish, corals, anenomes)
  • * Platyhelminthes (flatworms)
  • * Nematoda (roundworms)
  • * Mollusca (bivalves, squid)
  • * Annelida (segmented worms)
  • * Arthropoda (arachnids, crustaceans, insects)
  • * Echinodermata (starfish, urchins)

What is the basis of classification of Protochordata?

Classifications of Protochordata Protochordata are divided into three most important sub-categories based on the kind of notochord they possess, namely Hemichordata, Urochordata and Cephalochordata.

Why Urochordata and Cephalochordata are called Protochordata?

Phylum chordata of animal kingdom is divided into 2 sub-groups protochordata/acraniata(without brain box or cranium) and euchordata/craniata( cranium is present). Urochordata and cephalochordata which are acraniates are considered as primitive and often referred to as protochordates or non-vertebrate chordates

What are Protochordates give two examples?

Examples of protochordates are Balanoglossus, Saccoglossus, Herdmania, Amphioxus, Doliolum, Salpa etc

What are Urochordates give outline classification?

The Subphylum Urochordata includes a large number of species which exhibit high degree of biological diversities. The members are classified under three classes: Ascidiacea, Thaliacea and Larvacea or Appendicularia. Class Ascidiacea [Gk. Ascidians are marine and benthic forms which vary greatly in size and form.

What are the examples of Urochordata?


What are the three classes of subphylum Urochordata?

Classification of Urochordata: This subphylum is divided into three classes — Ascidiacea, Thaliacea and Larvacea.

What is the difference between Urochordata and Cephalochordata?

The main difference between Urochordata and Cephalochordata is that Urochordata consists of a notochord extended in the head region whereas Cephalochordata contains the notochord in the posterior region of the body