What is Hemichordata 3. What is Chordata 4. Similarities Between Hemichordata and Chordata 5. Hemichordata is a phylum of Kingdom Animalia. It includes animals that live in marine environments and those who consume sediments and dissolved organic matter as their foods.
They are worm-like deuterostome animals. They possess an epidermal nervous system. All the marine animals in the phylum hemichordate are invertebrates. This phylum is considered as a sister group of Echinodermata. There are three main classes of hemichordate. They are Enteropneusta, Pterobranchia and Planctosphaeroidea.
Class Enteropneusta contains acorn worms. Class Pterobranchia includes graptolites while class Planctosphaeroidea includes a single species that was identified by its larvae. Phylum hemochordata contains approximately living species. Animals of the hemichordate are bilaterally symmetrical, and the body can be divided into three sections; proboscis, collar and the trunk.
Their reproduction is mainly by sexual means. Their body cavity is a true coelom and posses a partially open circulatory system. Their excretory organ is glomerulus. Chordata is a phylum of Kingdom Animalia.
It is the phylum that includes humans and other familiar animals that are highly evolved. Phylum Chordata consists of animals that possess several characteristic features such as the presence of notochord a stiff, dorsal supporting rod , a dorsal hollow nerve cord and paired pharyngeal gill slits. It includes both vertebrates such as fish, amphibians , reptiles, birds and mammals and invertebrates that live in water, land and air in all most all major habitats. Chordata animals reproduce mostly by the sexual reproduction.
Some species show asexual reproduction as well. These animals possess a central nervous system, well-developed coelom, complete digestive system, cartilaginous endoskeleton and closed blood system.
Their body shows a bilateral symmetry, and the body is segmented. There are three subphyla in the phylum chordate. There are more than living species in this phylum under several categories such as fish, amphibians, reptiles, birds, mammals, salps, sea squirts and lancelets etc. Hemichordata and chordate are two phyla of animals. Hemichordata includes marine animals. Chordata includes advanced animals that possess a backbone.
They live in all major habitats. Both phyla are closely related, and they show a similar body plan. Both groups are deuterostomes. Both groups contain animals with bilateral symmetrical bodies. Hemichordata animals posses an epidermal nervous system while chordate animals possess a central nervous system.
This is the difference between Hemichordata and Chordata. You can download PDF version of this article and use it for offline purposes as per citation note. The circulatory system of hemichordates bears a heart-like, contractile vesicle. It is an open circulatory system with blood vessels and sinuses. The pharyngeal gill slits are used to capture small food particles by non-vertebrate chordates. A hemichordate is shown in figure 1. Enteropneusts are acorn worms that live in shallow water.
Pterobranchia contains colonial tube-like worms that live in an externally secreted encasement. Planctosphaeroidea contains planktonic organisms with spherical bodies covered with ciliary bands. Chordata refers to an animal phylum that contains a notochord, dorsally situated central nervous system, and gill slits.
Chordates can be found in freshwater, marine, and terrestrial habitats. All chordates possess a notochord, dorsal nerve cord, pharyngeal gill slits, and a post-anal tail at some point in their life. The notochord is a rod-like, elongated structure, which occurs dorsal to the gut and ventral to the nerve cord. The nerve cord is a dorsal and hollow. The central nervous system of chordates consists of a brain and a spinal cord. The peripheral nervous system connects the body to the central nervous system.
The pharyngeal gill slits occur in the pharyngeal portion of the gut. The notochord, nerve cord, and gill slits are shown in figure 2. Urochordate larva contains the notochord, nerve cord, and the post-anal tail. The adult urochordates are planktonic or sessile. The urochordate body occurs inside a tunic. The body of the Chelochordata is laterally compressed and transparent. Chelochordates present notochord, nerve cord, pharyngeal gill slits, and post-anal tail.
In Vertebrata, the notochord is covered by the vertebral column. The vertebral column provides axial support. The anteriorly modified skeleton produces the skull, which protects the brain. Hemichordata: Hemichordata refers to a phylum which contains worm-like marine animals with a proboscis as an outgrowth of the pharyngeal wall.
Chordata: Chordata refers to an animal phylum which contains a notochord, dorsally situated central nervous system, and gill slits. Hemichordata: Hemichordata mostly lives in marine habitats. Chordata: Chordata lives in marine, freshwater, and terrestrial habitats. Hemichordata: Hemichordata contains an epidermal nervous system.
Chordata: Chordata contains a central nervous system. Hemichordata: Hemichordata does not contain a notochord. Their nervous tissue is concentrated at the collar. Chordata: Chordata contains a dorsal, tubular notochord. Hemichordata: Hemichordata lacks a post-anal tail. Chordata: Chordata contains a post-anal tail. Hemichordata: Hemichordata contains an open circulatory system with dorsal and ventral blood vessels.
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