ectoderm

American  

[ek-tuh-durm] / ˈɛk təˌdɜrm /

noun

Embryology.

1. the outer germ layer in the embryo of a metazoan.

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ectoderm British  

/ ˈɛktəʊˌdɜːm /

noun

1. the outer germ layer of an animal embryo, which gives rise to epidermis and nervous tissue See also mesoderm endoderm

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ectoderm Scientific  

/ ĕk′tə-dûrm′ /

1. The outermost of the primary germ layers of an animal embryo. In vertebrates, the ectoderm gives rise to the epidermis and associated tissues (such as hair and sweat glands), enamel of the teeth, sense organs, nervous system, and lining of the nose, mouth, and anus.

2. Compare endoderm mesoderm

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Other Word Forms

• ectodermal adjective
• ectodermic adjective
• ectodermoidal adjective
• subectodermal adjective
• subectodermic adjective

Etymology

Origin of ectoderm

First recorded in 1860–65; ecto- + -derm

Example Sentences

Moreover, the developmental pathway through surface ectoderm state to amniotic ectoderm state was also observed in primate embryos.

From Science Daily • Mar. 4, 2024

Also, single cell RNA sequencing analysis suggested the differentiation pathway for amniotic ectoderm, where surface ectoderm genes are expressed before the activation of the amniotic ectoderm gene programme.

From Science Daily • Mar. 4, 2024

In an unexpected twist, no part of the sea star ectoderm expresses a "trunk" genetic patterning program, suggesting that sea stars are mostly headlike.

From Science Daily • Nov. 1, 2023

Outside this digestive cavity are three tissue layers: an inner endoderm, a central mesoderm, and an outer ectoderm.

From Textbooks • Jan. 1, 2015

The egg of Hydra is said to be fertilized as it lies at the base of the ectoderm, through which the fertilizing spermatozoon bores its way.

From Freshwater Sponges, Hydroids & Polyzoa by Annandale, Nelson

Related Words

• fur
• leather
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