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Where is the thorax located in the human body

The abdominal exoskeleton is multi-segmented. Each of the 10 segments is comprised of a ring of a hard material called chitin. The segments are linked by flexible tissues, allowing the abdomen to bend, a necessity for copulation and egg-laying. Reproductive organs. The genitalia are at the tip of the abdomen.

Each species has uniquely shaped genital armature - the male "key" only fitting the correct female "lock".

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Because the armature is unique to each species, taxonomists have traditionally relied heavily on microscopic examination of genitalia to determine species and their relationship with other taxa. The advent of DNA analysis and advances in phylogenetics however now mean that genitalia study is just one of many techniques adopted. Females are equipped with an ovipositor, used to release and deposit the fertilised eggs.

In most species this is short and not normally visible, but in certain moths it is modified into a long "sting-like" tube so that the eggs can be inserted into chinks in the bark of trees. The males of many neotropical Arctiid moths, including Creatonotos transiens possess at the tips of their abdomens an extraordinary eversible organ called a coremata. An unmated female "call" to males by releasing pheromones from the tip of her abdomen.

Males are attracted by the scent and arrive on the scene, forming a lek, often comprising of a dozen or more individuals. Experiments have demonstrated that males which have accumulated plant-derived pyrrolizidine alkaloids PAs then respond by everting their coremata and releasing pheromones.

The PAs are passed to females in a spermatophore during copulation, conferring them with toxic qualities that protect them from predation, and also increasing their longevity and fecundity.

Where are the Kidneys and Liver Located?

Captive males that have been deprived of PAs do not evert their coremata or release pheromones. It seems likely therefore that the females are able to select which males to mate with on the basis of the strength of their pheromones - i. On the sides of each segment are microscopic holes called spiracles, through which air enters and leaves the body. Slight rhythmic movements of the body, coordinated with the opening and closing of the spiracles, causes air to be drawn into tiny lung-like sacs, and later expelled. Digestive system. Butterflies feed exclusively on liquids which may according to species include nectar, dissolved pollen, mineralised water, liquefied dung, urine, sweat, bodily fluids from decomposing animal corpses, and in some cases even tears from the eyes of alligators!

After digestion and extraction of proteins and other minerals the waste matter is expelled from the anus either in liquid form, or as tiny faecal pellets. Sound producing organs. Insects such as cicadas and grasshoppers are well known for producing courtship songs, but most people only associate other insects with "incidental" sounds such as the buzzing of wings. There is a great deal of evidence however that insects in general, including lepidoptera, produce sounds that fulfil a variety of functions. Many of these sounds are beyond the range of human hearing, and can only be detected with specialised acoustical equipment.

In some butterflies however the sounds are clearly audible. Hamadryas butterflies can produce a crackling sound by twanging 2 tiny prongs on the tip of their abdomens against bristles on the valvae. This is discussed further on the next page. Nocturnal moths are commonly preyed upon by bats, which project a series of ultrasound clicks and listen to their echoes in order to locate flying moths.

Many moths have developed "ears" on their wings or thorax which can alert them to approaching bats, enabling them to take evasive action. The neotropical tiger moth Bertholdia trigona goes a stage further - it actively jams the bats "radar" by producing its own ultrasound, by vibrating a tympanal organ located on its metathorax. Within the thoracic cavity of flying insects are very powerful muscles which lever on the wings.

The rapid expansion and contraction of the muscles causes the wings to rise and fall at rates of up to beats per second in bees and hoverflies, and about beats per second in hawkmoths. Legs All adult butterflies have 3 pairs of legs, except in the Nymphalidae and in males of certain other groups, where the front pair are reduced to brush-like stumps and modified as chemoreceptors. Reproductive organs The genitalia are at the tip of the abdomen. Coremata The males of many neotropical Arctiid moths, including Creatonotos transiens possess at the tips of their abdomens an extraordinary eversible organ called a coremata.

Spiracles On the sides of each segment are microscopic holes called spiracles, through which air enters and leaves the body. Digestive system Butterflies feed exclusively on liquids which may according to species include nectar, dissolved pollen, mineralised water, liquefied dung, urine, sweat, bodily fluids from decomposing animal corpses, and in some cases even tears from the eyes of alligators! In the rat, perivascular adipose tissue in the abdomen express more inflammatory genes and markers of immune cells than the perivascular fat in the thorax, possibly because the abdominal adipose tissue has white adipose tissue characteristics, whereas in the thorax it is beige Padilla et al.

The responses of mediastinal SALCs and thoracic fluid to inflammogenic stimuli, mostly inhaled or instilled particles, are summarized in Box 2 rat and mouse; Bernstein et al. Acceleration of fluid flow happens by widening of already opened stomata and opening of formerly closed stomata, by increased drainage of the pleural interstitium and by increased diffusion and transcytosis Bodega and Agostoni, ; Li and Li, Flat mesothelial cells become cuboidal and release inflammatory mediators mouse; thoracic serosa ; mesothelial cells may proliferate rat, mouse; pleura. The fluid flow from the cavities into the lymphatics accelerates rat; pleural space , and harbor increased numbers of inflammatory cells rat; pleural space.

Macrophages are recruited and activated, comparable to alveolar macrophages rat; pleura, pleural space. Black spots on the parietal pleura can be anthracotic SALCs, whereas hyaline pleural plaques, associated with exposure to asbestos, may be anthracotic SALCs or inflammatory processes on the parietal pleura as a result of blockage of the stomata by fibers Murphy et al.

Based on the stimulus, either mainly thoracic or abdominal SALCs react. For example omental SALCs reacted much more than pleural SALCs upon percutaneous injection with Schistosoma mansonii in mice, a nematode with preference to the mesenteric veins Panasco et al. The opposite happened upon a subcutaneous injection with Litomosoides sigmodontis, a nematode that resides in the pleural cavity Jackson-Jones et al. Particles and particle-containing phagocytes are thought to be removed from the pleural space via the stomata and associated lymphatic channels, but Lehnert questioned this route as the only or most important pathway.

Based mainly on rat and some mouse and human data, he hypothesized that the caudal mediastinal tissue acts as the primary site via which particle-containing phagocytes are removed from the pleural space, to end up in the local LNs.

Diseases can also affect SALCs. The size of SALCs correlated well with immune cell infiltration in the lungs.

Chest Part 1: Thoracic wall dissection anatomy description; Amazing Human Body

Pleural fluid cell numbers are increased in humans and mice with systemic autoimmune diseases Pfau et al. The serosal immune system has unique anatomic and morphologic features, namely the lymphoid structures SALCs , the large quantity of innate B1 B and ILC2 lymphoid cells and the lymphatic drainage units.

The immune physiology of the serosal cavities is still poorly understood and many questions still remain. Do the abdominal and thoracic cavities co-operate like the respiratory tract and gut in the mucosal immune system? The different cavities start as 1 celom in embryonic life, but after birth there is no bulk flow between the pleural and peritoneal cavities Grimaldi et al. Still, ip-injected material in the rat is rapidly transported through lymphatics to the LNs in the mediastinum Shibata et al. Moreover, experiments with nematode-infected mice suggest that the cavities act largely as independent environments Panasco et al.

Interestingly in animals with an undivided celom, like for example insects, the serosal epithelium is immune-competent and expresses many genes involved in bacterial recognition and transduction of this recognition to receptor activation Jacobs et al.

As such, it is especially involved in acute and mainly innate immune responses. Thus, the serosal immune system operates in a unique way at the interface of the innate and acquired immunity. In addition, evaluation of potential toxicity to SALCs can increase our understanding of the normal physiology of these clusters. Knowledge of SALCs locations, the variation in their morphology and their position in the serosal immune system is a first step to examine their response to exposure.

Organs of the Thorax - TeachMeAnatomy

The authors would like to thank Fariza Bouallala for her enthusiastic and valuable efforts at the early stage of the project and Darryl Leydekkers, Lisanne Meijer, Tim van Olmen, and Eva Rennen for their expert technical contribution. Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide.

Sign In or Create an Account. Sign In. Advanced Search. Article Navigation. Close mobile search navigation Article Navigation. Volume Article Contents. E-mail: frieke. Oxford Academic. Google Scholar. Jolanda van Bilsen. Marcel V W Wijnands. Cite Citation. Permissions Icon Permissions. Abstract The thoracic cavities receive increasing attention in toxicology, because inhaled fibers and nano particles can reach these cavities and challenge the local lymphoid tissues.

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Figure 3. Significant numbers, especially NHCs? Large numbers; the presence of B1a B cells in the rat is questionable? High endothelial venules and other blood vessels: Critical organizers in lymphoid organ development and function. Search ADS. Subclinical atherosclerosis is associated with epicardial fat thickness and hepatic steatosis in the general population. Evaluation of the fate and pathological response in the lung and pleura of brake dust alone and in combination with added chrysotile compared to crocidolite asbestos following short-term inhalation exposure. Contribution of lymphatic drainage through stomata to albumin removal from pleural space.

Adipose tissues as an ancestral immune organ: Site-specific change in obesity. Human mediastinal adipose tissue displays certain characteristics of brown fat. Pleural macrophage recruitment and activation in asbestos-induced pleural injury. Defensive mechanisms in the mediastinum, with special reference to the mechanics of pleural absorption.