primitive streak

noun

Definition of primitive streak

: an elongated band of cells that forms along the axis of a developing fertilized egg early in gastrulation and that is considered a forerunner of the neural tube and nervous system

Examples of primitive streak in a Sentence

Recent Examples on the Web In that transition, the embryo forms a furrow called the primitive streak and folds inward on itself while cells mature into different lineages that will later give rise to all the organs and tissues of the body. — Kelly Servick, Science | AAAS, "Elusive master organizer of human embryo growth seen for the first time," 23 May 2018

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“Primitive streak.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/primitive%20streak. Accessed 7 May. 2021.

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primitive streak

noun

Medical Definition of primitive streak

: an elongated band of cells that forms along the axis of an embryo early in gastrulation by the movement of lateral cells toward the axis and that develops a groove along its midline through which cells move to the interior of the embryo to form the mesoderm

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