extraembryonic mesoderm

extraembryonic mesoderm

Etymology: L, extra, outside; Gk, en + bryein, to grow, mesos, middle, derma, skin

any mesoderm in the uterus that is not involved with the embryo itself. Included are mesoderms in the amnion, chorion, yolk sac, and connecting stalk.

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mesoderm

the middle of the three primary germ layers of the embryo, lying between the ectoderm and entoderm; from it are derived the connective tissue, bone, cartilage, muscle, blood and blood vessels, lymphatics, lymphoid organs, notochord, pleura, pericardium, peritoneum, kidneys and gonads.

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extraembryonic mesoderm

located outside the developing embryo and forming its accessory organs.

paraxial mesoderm

adjacent to the mid line beneath the epiblast of the embryo which develop into somites.

somatic mesoderm

the outer layer of the developing mesoderm.

splanchnic mesoderm

the inner layer of the developing mesoderm.