restriction. n. 1. something that restricts; a restrictive measure, law, etc. 2. the act of restricting or the state of being restricted. 3. (Logic) logic maths a condition that imposes a constraint on the possible values of a variable or on the domain of arguments of a function.
The primitive gut that forms during gastrulation in the developing embryo is known as the archenteron or the digestive tube.It develops into the digestive tract of an animal.ach is controlled by the dorsal blastopore, and primitive node (also known as Hensen's node), respectively. During Gastrulation, the Archenteron develops into the digestive tube, with the blastopore developing into either the mouth (Protostome) or the anus (Deuterostome).
Primitive reflexes are mediated by extrapyramidal functions, many of which are already present at birth. They are lost as the pyramidal tracts gain functionality with progressive myelination. They may reappear in adults or children with loss of function of the pyramidal system due to a variety of reasons.