chordates subphylum, Definition, Characteristics, classification, classes

What is it and its chordates subphylum

1. Definition

Chordata is a phylum or so-called group of animals has Notocord pliers (body axis) on the back. Phylum Chordata has several sub-phyla, such as subphylum Vertebrata, subphylum Urochordata, subphylum hemichordate, subphylum cephalocordata classified Invertebrates. Subphylum Vertebrata is a subphylum frequently encountered daily life. Unlike the other subphylum that some were already extinct and relatively primitive. Chordates alone has more species there are approximately 75,000 species worldwide

2. Characteristics

Besides notocord located in the dorsal or called back are hard and rigid, there are several other features that stand out in chordates, among others:
1. Tali hollow nerve, pharyngeal slits (pharyngeal alits), endostyle and muscular tail that passed through the anus.
2. Symmetrical bilateral, which was split into two when the symmetry it will be the same in each part.
3. In addition, there are three parts of the germ, sefilisasi centered in the head, then segmented body-segments, triploblastik conditions (eg dimensions ectoderm, mesoderm example blood vessels, for example, gut endoderm). and coelomic the breed.
4. Segment or body parts are metameri (each segment there is the same organ)
5. The existence of neural tube corda located in areas dorsals of the notochord. Internal and external fertilization (frogs and fish).
6. Tool on each animal digestion referred chordates located from the mouth to the anus. Then respiratory gills or lungs but there is also the skin that takes place behind closed doors.

3. classification

Separation of each subphylum of chordates seen by notocord that of the animal itself. There are 4 subphylum of chordates itself from vertebrates (have vertebrae) that we often encounter, subphylum hemichordate (presence or absence of the head) Urochordata (short stature) cephalochordates (lencelet). Below is described one by one

4 Chordata classes include:

- Subphylum hemichordate: an animal that has an elongated body shape like a worm. His body was small and too soft, these worms usually live seabed areas, sand and mud, diaceous reproductive organs, fertilization externally due to the area of his life on the waterfront. The neural networks are in the dorsal and venral. Notochorth short sized anteriorly. For example Balanoglosus, marine worms.

- Subphylum Urochordata: is a short-sized animal habitat of the region trpis, characteristic of chordates grow a tail section and after mature Urochordata notochor will disappear or heluecord basin. Living in colonies, sexual reproduction, and some are asexual (budding) then hemaprodit. This animal lives are parasites on fish or other animals that exist in the sea. Examples: molgula sp

Subphylum Cephalocordata: notochord is that there are areas chepal usual this animal called the lancelets. There are about 32 species that are on the earth. Characteristic of this animal shaped like a fish, do not have fins or a clear head, a separate sex (diaceous) external fertilization, has Isang pharyngeal slits (contained in faning). Segmented slender body, nortokord and elongated chordae nerves throughout the body. A place of life almost equal to the area above the shallow waters of chordates.

- And finally the most ubiquitous and still alive is subphylum vertebrates: Vertebrates is the largest sub-phylum of chordates. This vertebrate animals have a body structure that is much more perfect than invertebrates. Vertebrate animals consists of five classes, namely Pisces, amphibians, reptiles, aves and mammals. Classification of vertebrates based on: Poda (locomotor) consisting of a super class pisces and tetrapods. Cranium acraniata super class. And jaw gnatum consists of a super class Agnatha and gnatustoma. subfium has vertebrae (vertebrae) which is a modification of notocord own. Where they live anywhere, starting at sea, and land, it can be distinguished head, body, and means motion, because its shape is clear. Breathe with gills or lungs but in frogs (amphibians) there that breathes life cycle using the skin even if coupled with the lungs. Reproductive and sexual pairs also internal and external fertilization. Her heart was modern because the breed well, this can be seen from the division of the existing space. Starting from the right chamber and left, as well as the right and the left. Has a pair of eyes and ears and also own blood hemoglobin to transport oxygen. The body frame (endoskeleton) is formed of cartilage and true, the frame is attached to the muscle, discharge system consists of the kidneys, amounting pairs, nervous system consists of the brain and spinal marrow.

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