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Related to thoraces: macrocyte


body division found in certain animals. In humans and other mammals it lies between the neck and abdomen and is also called the chest. The skeletal frame of the thorax is formed by the sternum (breastbone) and ribs in front and the dorsal vertebrae in back. Within the thoracic cavity are the heart, lungs, and esophagus. The chest and abdominal cavities are separated by a muscular structure, the diaphragm. In insects and other arthropods the thorax is a body division consisting of several segments lying between the head and abdomen, to which are attached legs or other appendages.



the upper (in humans) or anterior (in most vertebrates) part of the trunk.

The shape of the thorax is determined by its skeleton—the chest and pectoral girdle—and by the muscles arranged on its surface. In arthropods the thorax is the section between the head and the abdomen. In primitive crustaceans (for example, Phyllopoda) the segments of the thorax are numerous and not constant in number; they bear nonspecialized appendages, equipped simultaneously for swimming, chewing, and breathing (gills). In higher crustaceans the number of segments of the thorax is reduced to between four and eight and becomes constant; part of the segments fuse with the head and their appendages become maxillipedary. In Arachnida and Xiphosura the segments of the thorax bear four pairs of gressorial legs and are usually merged with the head into a cephalothorax. In insects the thorax consists of three segments (prothorax, mesothorax, and metathorax), to each of which is attached a pair of legs; in higher insects one pair of wings each is attached to the mesothorax and metathorax in the adult stage.


The chest; the cavity of the mammalian body between the neck and the diaphragm, containing the heart, lungs, and mediastinal structures. Also known as thoracic cavity.
(invertebrate zoology)
The middle of three principal divisions of the body of certain classes of arthropods.


1. the part of the human body enclosed by the ribs
2. the corresponding part in other vertebrates
3. the part of an insect's body between the head and abdomen, which bears the wings and legs
References in periodicals archive ?
landolti by Jaffe & Navarro (1985), 4) Nestmate thoraces odorized with MG alien extract received more agonistic interactions than the thorax odorized with MG nestmate extract; and 5) Dummies odorized with MG alien extract received more agonistic interactions than dummies odorized with nestmate MG extract.
Antenatal routine ultrasound demonstrated janiceps conjoined male twins with a single fused cranial vault, duplicated cerebra, two faces (one well formed and other rudimentary), fused thoraces, two hearts, two completely separate spines, eight limbs and polyhydramnios.
Eulaema species are large, black and have densely pubescent thoraces and Euglossa species are smaller, lack external pubescence and are brightly colored, metallic blue or green (Rebelo 2001).
A total of seven informative allozyme loci were scored from the thoraces of each of the 1425 queens collected.
All wasps resident on nests were individually marked with enamel paint on their thoraces.