Ectoderm

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Ectoderm
Organs derived from ectoderm.
Section through embryonic disk of Vespertilio murinus.
Gray's	subject #6 48
MeSH	Ectoderm

The ectoderm is the start of a tissue that covers the body surfaces. It emerges first and forms from the outermost of the germ layers.

Contents 1 What forms from it (general)? 2 What forms from it (vertebrates)? 3 Additional images 4 References 5 See also

[edit] What forms from it (general)?

• Nervous system
• Outer part of integument

[edit] What forms from it (vertebrates)?

In vertebrates, the ectoderm has three parts: external ectoderm, the neural crest, and neural tube.

• External Ectoderm
  • skin (along with glands, hair, nail (anatomy))
  • epithelium of the mouth and nasal cavity
  • lens and cornea of the eye
  • Apical Ectodermal Ridge inducing development of the limb buds of the embryo.

• Neural crest
  • pigment cells in the skin
  • ganglia of the autonomic nervous system
  • dorsal root ganglia.
  • schwann cells
  • facial cartilage
  • dentin (in teeth)
  • spiral septum of developing heart
  • ciliary body of the eye.

• Neural Tube
  • brain (rhombencephalon, mesencephalon and prosencephalon)
  • spinal cord and motor neurons
  • retina
  • posterior pituitary

[edit] Additional images

Section through ovum imbedded in the uterine decidua

[edit] References

• Evers, Christine A., Lisa Starr. Biology:Concepts and Applications. 6th ed. United States:Thomson, 2006. ISBN 0-534-46224-3.

[edit] See also

v • d • e Mammalian development of embryo and development of fetus (some dates are approximate - see Carnegie stages)

Week 1: Zygote - Morula - Blastula/Blastomere/Blastosphere - Archenteron/Primitive streak - Blastopore - Allantois - Trophoblast (Cytotrophoblast - Syncytiotrophoblast - Gestational sac) Week 2: Yolk sac - Vitelline duct - Bilaminar disc Week 3: Hensen's node - Gastrula/Gastrulation - Trilaminar embryo Branchial arch (1st) - Branchial pouch - Meckel's cartilage - Somite/Somitomere - Sclerotome - Myotome - Germ layer (Ectoderm, Endoderm, Mesoderm, Chordamesoderm, Paraxial mesoderm, Intermediate mesoderm, Lateral plate mesoderm, Splanchnopleure, Somatopleure) Histogenesis and Organogenesis Glands: Thyroglossal duct Uterine support: Placenta - Umbilical cord (Umbilical artery, Umbilical vein, Wharton's jelly) - Amniotic sac (Amnion, Chorion) Limb development: Limb bud - Apical Ectodermal Ridge/AER