Arthropoda arthropoda The largest one the animal kingdom. Including the well-known shrimp, crabs, spiders, mosquitoes, flies, centipedes and other extinct trilobites. About 100 thousand species worldwide, accounting now for 75% of biological species. Symmetrical on both sides of the body. Constituted by the one body segment, different law section, can be divided into head, thorax, abdomen 3, or head to head and chest healing chest, abdomen or chest and healing for the trunk, each body segment has a pair of sub-section appendages. Appendages have a single-branch type and branch type categories. Important feature of arthropods in vitro covered with exoskeleton of chitin, also known as the epidermis or cuticle. In the body of the joint between the adjacent membrane, the cuticle is very thin, easy-to-inflected activities. Appendages movable joints. During the growth of arthropods molt regularly. Between the two stages before and after the molt is called age. Circulatory system is open tube. The respiratory organ of aquatic species for the gills or book gills, terrestrial or book for the trachea or both lungs. Primitive arthropod gas exchange by the body surface. Nervous system, the nervous system for the centralized chain. With touch, taste, smell, hearing, balance and vision and other sensory organs. Eye has two kinds of monocular and compound eyes. A hole formed by the compound eyes, capable of sensing the movement of external objects and shapes, can adapt to light intensity and identify colors. Most arthropods dioecious. Standing of terrestrial species in vivo fertilization, but there are many aquatic species for the in vitro fertilization. Generally oviparous, there are ovoviviparous; addition, parthenogenesis, reproductive and larval form of multi-embryo reproduction. Very wide range of arthropods living environment, whether it is sea water, fresh water, soil and air have their tracks. Some species also parasitic on other animals in vivo or in vitro. Arthropoda sub 4 sub door: extinct animals sub clover door, the existing animal subphylum limb claws, crustaceans and single-branch animal Amon Amon, 19 under the sub-classes, such as trilobites Programme (in cold Wu Ji, Ordovician height), crustaceans, limb port Programme (ie, leg mouth Gang), arachnids (fossil not much), the original tracheal classes, and more full classes (not more than fossils) and Insecta. Paleozoic trilobites especially the most important. Fossil arthropod exoskeleton can be formed. From the back some 7 to 10 million years ago, already Ediacaran fauna found in the fossil arthropods, beginning from the Early Cambrian trilobites appeared in large numbers. Many fossils have been used as a standard fossil arthropods stratigraphic correlation and instructions for the sedimentary environment. Arthropoda main gate and sub-classes are as follows: The original arthropod subphylum (protoarthropoda) Trefoil Amon (trilobitomorpha) Trefoil Programme (trilobitoidea) trilobites Programme (tirlobita) Crayfish limb Amon (chelicerata) Limb mouth Gang (merostomata) Kennedy Kok spider Amon (pycnogonida) Jawed Amon (mandibulata) Crustacea (crustacea) Insecta (insecta)
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The main features of the door
节肢动物门 门的主要特征
A physical distribution For example: Insecta (grasshopper): head, thorax, abdomen three parts; crustacea (shrimp): head and chest, abdomen two parts; arachnids (spiders): head and thorax, abdomen; more than enough classes (centipede): head , trunk. Division in the physiology of the body also appeared on the division of labor: Head: sensory and feeding centers Chest: Movement and Support Center Abdomen: Nutrition and breeding center Section 2 appendages, arthropod appendages are arranged by section, and part of the animal appendages foot warts, compared with significant progress: Foot warts comparison with arthropods: Arthropod foot warts Distribution by section and number of cloth a small number of body parts Standardized form and diverse forms With no joint between the appendages of the body section of the body, regardless of the relevant section between the section of appendages No large number of muscles attached to the muscle attachment 3 has developed striated muscle: arthropods between muscle and body wall muscles do not form a continuous layer, but the development of isolated muscle bundles. In previous animal arthropod muscles are smooth muscle, striated muscle began to form from arthropods to obtain highly developed motor function. 4 body was contained chitinous exoskeleton Body wall containing chitin is an important feature of arthropods. Arthropod body wall has a certain hardness, plays a supporting role equivalent to bone, it is called the exoskeleton. Chitin is a nitrogen-containing polysaccharide compounds acetic acid amide glucose. Chitin embedded in a grid-like structure of the protein matrix. The physical properties of chitin is soft, with a certain degree of flexibility and toughness. Chitin and protein together form the main component of arthropod body wall. Body wall rigidity is not due the presence of chitin, but because of the role of the enzyme protein under the tanning and hardening of. Hard exoskeleton limits growth of the body, it has shed phenomenon. 5 Respiratory diversity: arthropod respiratory forms, with different ecological groups and a series of changes: (1) body wall: inferior small crustaceans such as Daphnia. (2) Gill: aquatic crustaceans base in the foot protruding out from the body wall of the structure of thin film, full of capillaries. Such as shrimp and crabs. (3) book gill: the base of the body wall by the foot protruding out the pages folded into shape, with blood vessels. For aquatic species Limulus respiratory organs. (4) book lungs: depression by the body wall folds inward into the pages like, for the terrestrial arthropods spiders, scorpion respiratory organs. (5) trachea: the body wall invagination formed by the branches of tubular structures, for terrestrial arthropod insects, millipedes, centipedes and other respiratory organs. Distribution is no capillary tube, directly to oxygen to breathe organizations. Although the diversity of arthropod respiratory system, but they are a derivative of the body wall. Respiratory organs of aquatic species are protruding outside the body wall Respiratory organs of terrestrial species are the body wall of the inward depression Respiratory mechanisms of two kinds: Tracheal system: directly to the oxygen to breathe organization, and cell gas exchange Other types of respiratory gas exchange through the capillary, and then complete the transfer of oxygen from the circulatory system task. 6 mixed pipe body cavity and the open circulatory system (1) mix chamber: Arthropods of the body cavity in the early developmental stage but also the formation of the mesoderm of the body cavity capsule, but in the continued development of the process, does not extend to a broad true body cavity, but the degradation of the reproductive lumen, excretion lumen and around chambers of the heart. During development in the future, parietal pericardial disappear, so that the body wall and the primary body cavity between the digestive tract and pericardial cavity mixed secondary body cavity, creating a hybrid body cavity. Cavity filled with a mixture of blood, mixed blood, also known as body cavity chamber. (2) open tubular circulatory system: the blood through the heart - → arteries - → blood chamber - → Heart Hole - → heart. Beating heart can be independent, have a certain direction of blood flow. The complexity of the arthropod circulatory system and respiratory system, the degree of complexity: Respiratory system is simple (limited to a body part), circulatory system complexity, such as shrimp. Respiratory complex (dispersed in various parts of the body), the circulatory system is simple, such as insects. Breathing with the body surface of small arthropod circulatory system disappeared, such as Daphnia. 7 Two types of excretory organs (1) and after homologous renal tubular glands: evolved from the tube after the kidney, such as crustaceans antennal gland, green gland, spider-shaped outline of the base section of glands and so on. Arthropods renal excretory organ of secondary closed mouth, and bladder by the Department of the Ministry of glands composed. Nitrogenous waste by the Department of infiltration into the glands, and then excreted by the Ministry of the bladder. (2) Ma tube: insects, spiders and other organs of the Malpighian tubules to excrete. Malpighian tubules from the digestive tract, hindgut outside the bowel wall at the junction of tubular structure formation processes. It is directly immersed in the blood uric acid and other nitrogenous waste in large numbers, into the hindgut, the excreted through the anus. Arthropoda sub 4 sub door: extinct animals sub clover door, the existing animal subphylum limb claws, crustaceans and single-branch animal Amon Amon, 19 under the sub-classes, such as trilobites Programme (in cold Wu Ji, Ordovician height), crustaceans, limb port Programme (ie, leg mouth Gang), arachnids (fossil not much), the original tracheal classes, and more full classes (not more than fossils) and Insecta. Paleozoic trilobites especially the most important. Fossil arthropod exoskeleton can be formed. From the back some 7 to 10 million years ago, already Ediacaran fauna found in the fossil arthropods, beginning from the Early Cambrian trilobites appeared in large numbers. Many fossils have been used as a standard fossil arthropods stratigraphic correlation and instructions for the sedimentary environment. 8 and sensory nerve 9, reproductive and developmental Arthropods is generally dioecious, male and female and often shaped. Usually internal fertilization, cleavage way is to split the table, there is direct development, but also indirect development. The types of indirect development from one to several different larval stage, and sometimes the living habits of these larvae and adults are different. Also some arthropods capable of parthenogenesis, that is not fertilized eggs can develop into adults. Arthropods are not asexual. Arthropoda main gate and sub-classes are as follows: The original arthropod subphylum (protoarthropoda) Trefoil Amon (Trilobitomorpha) Trefoil Programme (Trilobitoidea) trilobites Programme (Tirlobita) Crayfish limb Amon (Chelicerata) Arachnida (Arachnida) chelate leg one of the largest classes subphylum Limb mouth Gang (Merostomata) Amon Canal Point spider (Pycnogonida) Jawed Amon (Mandibulata) Crustacea (Crustacea) Insecta (Insecta) More foot Programme (Myriapoda)
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Arthropoda Classification
Arthropods are the largest animals a door, a total of 110 ~ 120 million existing species of animals, the total number of species accounted for 4 / 5. This animal's own classification system is still talking about so far, especially for more senior classes of all taxa relative to academics rather widely. In accordance with a combination of somites, limb, and respiratory and other tentatively divided into the following two sub-types of existing doors, 6 classes: l. of the original arthropod subphylum (Protarthropoda) Body, regardless of section, only the surface of the ring pattern. Appendages are not sub-section. Only one master plan (1) claw Programme (Onychophora), also known as the original pipe Programme (Prototracheata), such as the silkworm and so on. 2. True arthropod subphylum (Euarthropoda) Body section. Appendages can be divided into sections. A total of 5 classes. (2) limb port Programme (Merostomata) brain and abdominal body separately. Department heads have 6 on the attached plastic, that is, a pair of sting limb (chelicera), and 5 on pereiopod; no tentacles. Pleopod 7 pairs. Breathe with gills. Such as the horseshoe crab and so on. (3) Arachnida (Arachnoida) body separately chest and abdomen. Cephalothorax, 6 pairs of appendages, that is, one pair of supernumerary limb, a pair of legs to be (touch limb) (PalP = PediPalP) and four pairs of ambulatory leg; and no antennae. Pleopod is almost completely degraded. Book lung and tracheal breathing. Such as various spiders. (4), crustaceans (Crustacea) body often split up the brain and abdomen. Cephalothorax appendages 13 of them, namely, 5 and 8 head of thoracic limb limb. 5 head and limbs, including 2 pair of antennae, a pair of large jaw and 2 on the small jaw. 8 pairs of thoracic limb of the jaw in the first few feet, the rest of the pereiopod. Pleopod with or without. Breathe with gills. Such as a variety of shrimp and crabs. (5) Multi-foot Programme (Myriapoda) head and trunk volume fraction. 3 to 4 pairs of head appendages, that is, a pair of antennae, a pair of large jaw, and 1 to 2 small jaw. More on the pereiopod trunk, each body segment l-2 pairs. Tracheal breathing. Such as centipedes and so on. (6) Insecta (Insecta) body separately, chest, abdomen and head with four pairs of appendages, including a pair of antennae, a pair of large jaw, a small jaw and a pair of left and right to become a healing of the lower lip 3 pairs of pereiopod chest. Abdominal appendages almost completely degraded. Such as a variety of mosquitoes and flies.
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Arthropoda (fossil)
jiezhi dongwu men (huashi) Arthropoda (fossil) Arthropoda is the largest one the animal kingdom, its external skeleton to form fossils. From the back some 7 to 10 million years ago, already Ediacaran fauna found in the fossil arthropods, beginning from the Early Cambrian trilobites appeared in large numbers. Fossil arthropods in the past many fossils for stratigraphic correlation as the standard. Also can be used to indicate the depositional environment. Classification Classification of arthropods have had a variety of programs, the current sub-divided into 4 or 5 door is more common. 4 Amon means clover, crustaceans, crayfish limb and single-branch animal sub-door, five sub-angle of the door put the firm designated as an independent sub-door spider. Gates in a single sub-branch into a claw foot and six feet more than 3 Chaogang. There is also a direct into clover, chelate limbs, strong angle spiders, crustaceans, with claws, and more feet, six feet, tongue, slowly, etc. 9 Chaogang classification. In the six-foot Chaogang in the end will be the original, playing the tail, double tail, Ying Mei and other projects in the separation from the Insecta, as the program independently. With the discovery of the fossil material and present new findings and studies arthropod-depth, arthropod taxonomy in the future may also have a greater change. Extremely broad distribution of arthropod fossil distribution in different geological history of the different geographical areas are often a variety of insect fossils in sediments. In particular, there is shelling process because many arthropods, chitin shell so that it can form on the number of extremely rich fossil. To preserve the fine in a number of famous fossil site known for often can see a soft impression of the arthropod body fossils, such as the Ediacaran fauna of the Burgess fauna, horse gram grams of fauna and were recently discovered in the Chengjiang of China fauna and so on. Preserved in amber fossil insects is exquisite. Animals sub-clover fossil Arthropoda door is the largest category, which outline the most important trilobite, trilobites Gang first appeared in the early Cambrian, the Permian extinction (see trilobite) . Trefoil insects Programme (Figure 1 trilobal Programme on behalf of insect fossils (Waptia fieldensis)) located in the Cambrian to the Devonian, most of British Columbia in western Canada were collected from the Middle Cambrian Burgess Shale , save for the carbonaceous thin film, according to analysis, their way of life of both benthic and planktonic. Amon crayfish limb animal outline the original limb is also seen in the mouth of the Early Cambrian, the board foot horseshoe crab class to Permian extinction, fossils widely spread; sword tail classes of modern life there. Arachnida (Silurian ─ modern) and the Kennedy angle spider Amon (Devonian ─ modern) fossils are rare. Crustacean subphylum also appeared in the early Cambrian, until now, many are student representatives, including gill foot Gang conchostracans classes and classes in the fossil ostracods of the more important. A key link in the leaves of soft real shrimp and soft after the CPI from the Cambrian period, have been found in many times, China has also been found (Figure 2 Guizhou China bubble shrimp (Sinopemphix □ uizhouensis) carapace diagram, Figure 3, King of Taiwan s mantis shrimp (Won □ astacia taiwanica)). Man enough to outline the fossil barnacles (Balanus) as the representative. Gang copepods few fossils. Programme no reports of other fossils. Claws Chaogang, multi-foot and six foot Chaogang Chaogang former two rare fossils, which are mainly insect fossil fossil 〔see Insecta (fossil)〕. (Zhang Wentang)
insecta