Classification of urochordata
What are the classification of Urochordata?
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.
What are the three classes of urochordates?
The urochordates are subdivided into three classes: Ascidiacea, Thaliacea, and Larvacea.
What is the characteristics of Urochordata?
They have a shape of a bag, sessile and filter-feeding animals. They are found in seawater only. They have a nerve cord and notochord at the tail of their larvae. Both the nerve cord and the notochord are lost during metamorphosis.
What is Urochordata in zoology?
Urochordata (Tunicata) A subphylum of marine nonvertebrate chordates in which the body is typically enclosed in a protective tunic of a cellulose-like material and the notochord and dorsal hollow nerve cord are evident only in the free-swimming tadpole-like larval stage.
How many types of Urochordata are there?
Tunicate/Lower classifications
What are the classes of Cephalochordata?
The subphylum Cephalochordata comprises a single family Brachiostomatidae with two genera Branchiostoma (Costa, 1834) and Asymmetron (Andrews, 1893).
What is an example of Urochordata?
Tunicate/Lower classifications
What are urochordates give one example?
Urochordata is a subphylum of Chordata which includes the Tunicates and other classes such as Larvacea, Thaliacea etc. Tunicates or Urochordata are marine filter-feeding animals, found at all latitudes, and living mostly in shallow water. They are also known as “Sea Squirts”. An example of urochordata is Ascidia.
What is the function of Urochordata?
They are marine filter-feeding animals, found at all the latitudes, and can assume a planktonic or benthic lifestyle. They are, with few exceptions, hermaphroditic animals with an indirect development: almost all the tunicate species have a tadpole swimming larva.
What is the classification of Herdmania?
Stolidobranchia is an order of tunicates in the class Ascidiacea. The group includes both colonial and solitary animals. They are distinguished from other tunicates by the presence of folded pharyngeal baskets. This provides the etymology of their name: in ancient Greek, στολίς, ίδος means the “fold” of a cloth.
Which type of circulatory system is shown by urochordates?
Urochordates have an open circulatory system. Hence, the correct answer is option (C). Additional information: Hemichordates have long been considered the lowest group of Chordata that make up the notochord, nerve cord, and pharyngeal gill slits, the main feature of the phylum chordata.
Why urochordates are called tunicates?
It is also known as Tunicate because the body of an adult is enclosed within a tunic made up of a cellulose-like substance known as tunicin. It provides the urochordates with protection.
What is an example of Urochordata?
Tunicate/Lower classifications
Which organ filters food in Urochordates?
pharynx
Digestive System: Large pharynx with many gill slits (stigmata) for filter-feeding; food trapped in mucus; food tube short and simple, often U-shaped with anus near atrial siphon. Circulatory System: Blood system with sinuses in mesenchyme; heart reverses periodically. Locomotion: Usually adults are sessile.
Do Urochordates have heart?
Tunicates have a well-developed heart and circulatory system. The heart is a double U-shaped tube situated just below the gut. The blood vessels are simple connective tissue tubes, and their blood has several types of corpuscle.
Is heart present in Urochordata?
Heart is present on the dorsal side of the body of non-chordates. Heart if present in the non-chordates is on ventral side of body.
What Colour is tunicate blood?
This review covers three aspects of tunicate blood: its yellow/green pigmentation, vanadium content, and vacuolated blood cells. The yellow/green pigmentation is due to a class of organic compounds called tunichromes.
What is the excretory organ of Urochordata?
No special excretory organs appear to be present. Nitrogenous waste is excreted as ammonia, which by the exhalant flow of water and through diffusion, can be easily taken away from the general body surface. Hence, the correct answer is option (A).