Sclerotome

(embryology) The part of a mesodermal somite which enters into the formation of the vertebrae.
(medicine) A knife used in sclerotomy.
(vertebrate zoology) The fibrous tissue separating successive myotomes in certain lower vertebrates.

1. A knife used in sclerotomy.
2. A group of mesenchymal cells emerging from the ventromedial part of a mesodermic somite and migrating toward the notochord.

1. an instrument used in incision of the sclera.
2. the area of a bone innervated from a single spinal segment.
3. one of the paired segmented masses of mesenchymal tissue, separated from the ventromedial part of a somite, which develop into vertebrae and ribs.

Sclerotome
Scheme showing the manner in which each vertebral centrum is developed from portions of two adjacent segments.
Transverse section of a human embryo of the third week to show the differentiation of the primitive segment. (Kollmann.) ao. Aorta. m.p. Muscle-plate. n.c. Neural canal. sc. Sclerotome. s.p. cutis-plate.
Gray's	subject #17 80
Carnegie stage	10
Precursor	somite
Gives rise to	vertebrae

A sclerotome is part of a somite, a structure in vertebrate embryonic development. Sclerotomes eventually differentiate into the vertebrae and most of the skull. The caudal (posterior) half of one sclerotome fuses with the rostral (anterior) half of the adjacent one to form each vertebra.^[1]

From their initial location within the somite, the sclerotome cells migrate medially towards the notochord. These cells meet the sclerotome cells from the other side to form the vertebral body. From this vertebral body, sclerotome cells move dorsally and surround the developing spinal cord, forming the vertebral arch. ^[1]

References

1. ^ ^{a b} Walker, Warren F., Jr. (1987) Functional Anatomy of the Vertebrate San Francisco: Saunders College Publishing.

External links

• mslimb-008 — Embryology at UNC
• Diagrams at ciwemb.edu
• Embryology at UNSW Notes/week3_6

This developmental biology article is a stub. You can help Wikipedia by expanding it.

v • d • e Developmental biology > Human embryogenesis (development of embryo) and development of fetus First three weeks Week 1 Fertilization · Egg activation · Zygote · Cleavage · Morula · Blastula (Blastomere) · Blastocyst · Inner cell mass Week 2 (Bilaminar) Hypoblast · Epiblast Week 3 (Trilaminar) Germ layers Archenteron/Primitive streak (Primitive pit, Primitive knot/Blastopore, Primitive groove) · Gastrula/Gastrulation · Regional specification Ectoderm Surface ectoderm · Neuroectoderm · Somatopleure · Neurulation · Neural crest Endoderm Splanchnopleure Mesoderm Chorda- · Paraxial (Somite/Somitomere/Sclerotome/Myotome/Dermatome) · Intermediate · Lateral plate (Intraembryonic coelom, Splanchnopleure/Somatopleure) Extraembryonic/ uterus Trophoblast (Cytotrophoblast, Syncytiotrophoblast) Blastocoele · Yolk sack/exocoelomic cavity · Heuser's membrane · Extraembryonic coelom · Vitelline duct Umbilical cord (Umbilical artery, Umbilical vein, Wharton's jelly) · Allantois Placenta · Decidua (Decidual cells) · Chorionic villi/Intervillous space · Gestational sac (Amnion/Amniotic sac/Amniotic cavity, Chorion) Histogenesis Programmed cell death (Apoptosis) · Stem cells · Germ line development Organogenesis Limb development: Limb bud · Apical ectodermal ridge/AER other structures: Eye development · Cutaneous structure development · Heart development · Development of the urinary and reproductive organs (Some dates are approximate—see Carnegie stages and a timeline.)

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