ectoderm


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Related to ectoderm: mesoderm

ectoderm

 [ek´to-derm]
the outermost of the three primary germ layers of the embryo; from it are derived the epidermis and epidermic tissues such as nails, hair, and glands of the skin; the nervous system; external sense organs such as the eye and ear; and the mucous membranes of the mouth and anus. adj., adj ectoder´mal, ectoder´mic.

ec·to·derm

(ek'tō-dĕrm),
The outer layer of cells in the embryo, after establishment of the three primary germ layers (ectoderm, mesoderm, endoderm), the germ layer in contact with the amnionic cavity.
Synonym(s): ectoblast (1)
[ecto- + G. derma, skin]

ectoderm

/ec·to·derm/ (ek´to-derm) the outermost of the three primitive germ layers of the embryo; from it are derived the epidermis and epidermic tissues, such as the nails, hair, and glands of the skin, the nervous system, external sense organs and mucous membrane of the mouth and anus.ectoder´malectoder´mic

ectoderm

(ĕk′tə-dûrm′)
n.
1. The outermost of the three primary germ layers of an embryo, from which the epidermis, nervous tissue, and, in vertebrates, sense organs develop.
2. The outer layer of a diploblastic animal, such as a jellyfish.

ec′to·der′mal, ec′to·der′mic adj.

ectoderm

[ek′tədurm]
Etymology: Gk, ektos, outside, derma, skin
the outermost of the three primary cell layers of an embryo. The ectoderm gives rise to the nervous system; the organs of special sense, such as the eyes and ears; the epidermis and epidermal tissue, such as fingernails, hair, and skin glands; and the mucous membranes of the mouth and anus. See also embryo, endoderm, mesoderm. ectodermal, ectodermic, adj.

ec·to·derm

(ek'tō-dĕrm)
The outer layer of cells in the embryo, after establishment of the three primary germ layers (e.g., ectoderm, mesoderm, endoderm).
Synonym(s): ectoblast (1) .
[ecto- + G. derma, skin]

ectoderm

The outermost of the three primary germ layers of an embryo, the others being the MESODERM and the ENDODERM. The ectoderm develops into the skin, the nervous system, and the sense organs.

ectoderm

or

ectoblast

the germ layer lying on the outside of the developing embryo that eventually gives rise largely to the EPIDERMIS, but also to nervous tissue and, where present, nephridia (see NEPHRIDIUM). Compare ENDODERM.

ectoderm

primary germ layer of embryonic cells, forming epidermal structures and nerve tissue

ectoderm

The outermost of the three primary germinal layers of an embryo (the other layers being mesoderm and endoderm) from which the eye is derived. It differentiates into outer surface ectoderm and inner neuroectoderm, which gives rise to neural crest cells. The surface ectoderm gives rise to the crystalline lens, the lacrimal gland, the meibomian glands, the corneal and conjunctival epithelium and the epidermis of the eyelids. The neuroectoderm (neural ectoderm) will form the retina, retinal pigment epithelium, the pigmented and non-pigmented layers of the ciliary and iris epithelium, the dilator and sphincter muscles of the iris and the optic nerve fibres. Neural crest cells will form the corneal stroma and endothelium, sclera, iris and choroidal stroma, ciliary muscle and trabecular meshwork. See optic cup; mesoderm; optic vesicles.

ec·to·derm

(ek'tō-dĕrm)
Outer layer of cells in the embryo, after establishment of the three primary germ layers (ectoderm, mesoderm, endoderm).
[ecto- + G. derma, skin]

ectoderm

(ek´tədurm),
n the outermost of the three primary cell layers of an embryo. The ectoderm gives rise to the nervous system, the organs of special sense, the epidermis, and epidermal tissues such as fingernails, hair, and skin glands.

ectoderm

the outermost of the three primitive germ layers of the embryo; from it are derived the epidermis and epidermal derivatives, such as the claws, hair and glands of the skin, the nervous system, external sense organs (eye, ear, etc.) and mucous membrane of the mouth and anus.
References in periodicals archive ?
Wnt-7a is expressed in the dorsal ectoderm and upregulates the production of LIM homeobox transcription factor 1, alpha (Lmx-1), which in turn causes dorsal differentiation of the limb.
Separation of neural and surface ectoderm after closure of rostral neuropore.
The protein, Engrailed, is a transcription factor with known roles in controlling morphology and ectoderm differentiation, and functions to produce ectodermal boundaries to differentiate specific neurons and to pattern appendages in Drosophila development (Kornberg et al.
The whole organism is composed of three principal layers of tissue: the endoderm, the ectoderm, and the mesoderm.
This gene, expressed in tissues derived from ectoderm, encodes the transmembrane type II protein ectodysplasin.
SOX2, in contrast to POU5F1 and NANOG, is not down-regulated in early differentiation toward ectoderm [(31) and unpublished data].
They are able to differentiate into all derivatives of the three primary germ layers: ectoderm, endoderm, and mesoderm.
ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm, and mesoderm.
If the cells of the ICM are harvested and grown in appropriate culture conditions, however, they will replicate indefinitely and, when suitably stimulated, will differentiate into three germ layers: ectoderm, mesoderm, and endoderm--representing any cell lineage of the body.
This comprehensive collection of appropriate protocols takes the novice into consideration as contributors closely describe obtaining and culturing human ES cells, including explanations of derivatives of human ES cell lines as well as standard and chemically-defined culture methods, characterization of human ES cells, including phenotype, genetic and epigenetic analysis, manipulation in vivo and in vitro of human ES cells, including differentiation and repopulation, directed differentiation of human ES stem cells into ectoderm with forebrain and other neurons, and other issues such as gene targeting and RNA interference.
It must be able to divide asymmetrically, one daughter resembling its mother, the other daughter giving rise to multiple types of differentiated cells representing all three primitive embryonic germ layers (the ectoderm, mesoderm, and endoderm).
Formation of a nervous tube, a nervous crest, ganglios plates, placose, skin ectoderm, prechordial plate, and outer ectoderm finishes differentiation of primary ectoderm.