Neurulacja

Neurulacja is a fundamental process in embryonic development that establishes the initial structure of the central nervous system. It follows gastrulation, during which the three primary germ layers are formed. Neurulation begins with the formation of the neural plate, a thickened region of ectoderm situated along the dorsal midline of the developing embryo. This plate is induced by signals from the underlying notochord and mesoderm.

Following the formation of the neural plate, its edges begin to elevate, forming the neural folds. The space between these folds is called the neural groove. As development progresses, the neural folds continue to rise and eventually meet and fuse along the dorsal midline. This fusion seals the neural groove, transforming it into the neural tube, a hollow, cylindrical structure that will give rise to the brain and spinal cord.

During the fusion process, some cells from the crest of the neural folds detach. These cells, known as neural crest cells, migrate to various locations in the embryo and differentiate into a diverse range of cell types, including peripheral neurons, glial cells, melanocytes, and parts of the skull and face. The neural tube itself undergoes further differentiation, with its anterior portion expanding to form the brain vesicles and its posterior portion elongating to become the spinal cord. Defects in neurulation can lead to severe congenital abnormalities such as spina bifida and anencephaly.