cephalic flexure การใช้

ประโยค

The rhombomeres appear as a series of slightly constricted swellings in the neural tube, caudal to the cephalic flexure.
By the growth of the head end of the embryo, and the formation of the cephalic flexure, the pericardial area and the buccopharyngeal membrane come to lie on the ventral surface of the embryo.
The latter flexure mainly appears in mammals and sauropsids ( reptiles and birds ), whereas the other two, and principally the cephalic flexure, appear in all vertebrates ( the sum of the cervical and cephalic ventral flexures is the cause of the 90 degree angle mentioned above in humans between body axis and brain axis ).
However, the situation is more complex, since comparative embryology shows that the length axis of the neural tube ( the primordium of the brain ) has three internal bending points, namely two ventral bendings at the cervical and cephalic flexures ( cervical flexure roughly between the medulla oblongata and the spinal cord, and cephalic flexure between the diencephalon and the midbrain ), and a dorsal ( pontine or rhombic ) flexure at the midst of the hindbrain, behind the cerebellum.
However, the situation is more complex, since comparative embryology shows that the length axis of the neural tube ( the primordium of the brain ) has three internal bending points, namely two ventral bendings at the cervical and cephalic flexures ( cervical flexure roughly between the medulla oblongata and the spinal cord, and cephalic flexure between the diencephalon and the midbrain ), and a dorsal ( pontine or rhombic ) flexure at the midst of the hindbrain, behind the cerebellum.

cephalic flexure การใช้

ประโยค

คำอื่น ๆ