somite


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somite

 [so´mīt]
one of the paired segments along the neural tube of a vertebrate embryo, formed by transverse subdivision of the thickened mesoderm next to the midplane, that develop into the vertebral column and muscles of the body.
Somites in a 22-day embryo. From Dorland's, 2000.

so·mite

(sō'mīt),
One of the paired, metamerically arranged cell masses formed in the early embryonic paraxial mesoderm; commencing in the third or early fourth week in the region of the hindbrain, they develop in a caudal direction typically until 42 pairs are formed.
Synonym(s): mesoblastic segment
[G. sōma, body, + -ite]

somite

/so·mite/ (so´mīt) one of the paired, blocklike masses of mesoderm, arranged segmentally alongside the neural tube of the embryo, forming the vertebral column and segmental musculature.

somite

(sō′mīt′)
n.
1. Any of the homologous segments that compose the body of certain animals, such as earthworms and lobsters, and are arranged in a longitudinal series.
2. A segmental mass of mesoderm in the vertebrate embryo, occurring in pairs along the notochord and developing into muscles and vertebrae.

so·mit′ic (sō-mĭt′ĭk) adj.

somite

[sō′mīt]
Etymology: Gk, soma, body
any of the paired segmented masses of mesodermal tissue that form along the length of the neural tube during the early stage of embryonic development in vertebrates. These structures give rise to the vertebrae and differentiate into various tissues of the body, including the voluntary muscle, bones, connective tissue, and dermal layers of the skin. The first somite to appear is in the future occipital region, and the formation of new somites continues in a caudal direction until 36 to 38 have developed.

so·mite

(sō'mīt)
One of the paired, metamerically arranged cell masses formed in the early embryonic paraxial mesoderm; commencing in the third or early fourth week in the region of the hindbrain, they develop in a caudal direction until 42 pairs are formed; their presence is considered evidence that metameric segmentation is a vertebrate characteristic.
[G. sōma, body, + -ite]

somite

or

metamere

a serial segment of the animal body. see METAMERIC SEGMENTATION.

so·mite

(sō'mīt)
One of the paired, metamerically arranged cell masses formed in early embryonic paraxial mesoderm; develop in a caudal direction typically until 42 pairs are formed.
[G. sōma, body, + -ite]

somite

one of the paired block-like masses of mesoderm beside the neural tube of a vertebrate embryo, formed by transverse subdivision, that develop into the vertebral column, skin and muscles of the body.
References in periodicals archive ?
bipunctatus has a long dactylus inserted disto-medially on ventral margin of propodus and overreaching the tip of this latter article, and a subtriangular telson, laterally expanded, which is wider than the sixth somite (Figs.
To make the ventral fin acupuncture injury, a sterile pin was used at in the ventral fin area, 4-5 somites from the cloaca.
japonica stridulate by rubbing terga of somites while bracing themselves against the substrate and lifting their pleotelson to the dorsal side.
Studies in knockout of Nog shows abnormalities in the neural tube and the somites and mandibular defects ranging over a range of phenotypes from the mandibular hypoplasia, passing through an intermediate phenotype micrognathia (poor formation of the jaw) to agnathia (absence of mandibular formation) (88,89).
The abdomen of the larvae from the Atlantic coast of Mexico has dorsolateral processes on somite 5, which are absent in the Pacific population (Cuesta & Schubart 1999).
These alginate beads helped somites to retain their integrity in vitro without somite cell migration in our media as well as to continue their intrinsic gene expression and protein secretion activity.
In other Vespidae species analyzed, besides the increment in general structural size there are other recorded morphological alterations over larval development, such as: appearance of ventral lobes on the first abdominal somite on third-instar larvae of Mischocyttarus cassununga (Ihering) (Giannotti & Silva 1993), and the development of a subapical tooth on second-instar larvae of Polistes lanio (Fabricius) (Giannotti 1995).
In some previous studies, IRF6 gene of xenopus was found to be expressed as a maternal transcript and later in the posterior somite mesoderm of neural groove stage embryos, and IRF6 expression has been observed only in the ovary after adulthood was attained (Hatada et al.
Mullerian hypoplasia or aplasia - renal agenesis - cervicothoracic somite dysplasia known as the MURCS association (Mullerian duct aplasia; R: renal agenesis / ectopia; CS: cervical somite dysplasia) represent the most rare and severe form of the syndrome.
VGMs form during the late somite stages of the 4th week of embryonic life.