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 ?
aureus into the muscles of the fifth somite rostral from the cloaca, the number of neutrophils accumulated at the bacterial injection site at 2 hours post infection (hpi) was similar: 25.
Blocks of mesoderm positioned beside the notochord give rise to the muscles, limbs, spine and dermis, called somites, which segment, forming myomeres widely used in taxonomic studies of fishes (Araujo-Lima and Donald, 1988; Wolpert et al.
japonica stridulate by rubbing terga of somites while bracing themselves against the substrate and lifting their pleotelson to the dorsal side.
Noggin mediated antagonism of BMP signaling is required for growth and patterning of the neural tube and somite.
The sequence of the zoeal description is based on the malacostracan somite plan and described from anterior to posterior.
embryos were isolated from the yoW surface of the fertilized eggs and somites were subsequently isolated from embryos under a dissecting microscope.
6A), the numbers of notochord cells were 9 under three somites, while these were in 21 in V-AA treated embryos, 1 in V-ABA and 40 in V-APAA.
12 hours after the 9h6hr treatment time (late treatment), embryos have approximately 30 to 34 somites.
The occurrence of the MURCS association is sporadic, (4) and the etiology is still not clear; one hypothesis is that it results from an alteration of the blastema of the lower cervical and upper thoracic somites and pronephric ducts, which have an intimate spatial relationship in the fourth week of fetal development.
Fifteen hours post-fertilization, the embryo occupied 90% of the egg space, and the somites or primitive segmentation could be seen (Fig.