Neural tube.
The neural tube
Neural Tube
The neural tube develops into the vertebrate spinal cord. It forms early in embryonic development from a flat sheet of neural ectoderm that rolls into a tube, eventually differentiating into the brain and spinal cord.
The neural tube is the structure in mammalian embryos that develops into the brain and spinal cord. It forms from the ectoderm layer during development and gives rise to the central nervous system.
In the 3rd week of pregnancy called gastrulation, specialized cells on the dorsal side of the fetus begin to change shape and form the neural tube.
The first part to develop in a human is the neural tube, which eventually develops into the brain and spinal cord. This typically occurs during the third week of gestation.
The medical term for the inner diameter of a tube is "lumen."
A neural vesicle is an embryonic structure that gives rise to the brain and spinal cord. It is a hollow tube formed during early development that eventually develops into the central nervous system.
Spina bifida occurs during the first trimester. Spina bifida is in a class of birth defects known as neural tube defects. The neural tube eventually develops into the spinal cord, brain and the tissues that enclose them. In a normal pregnancy the tube forms early and closes by the twenty eighth day. With spina bifida portions of the neural tube fail to develop properly causing defects of varying severity in the spinal cord and back bones. This is a complicated topic and you can read more about it at the related link.
This occurs as a result of the folding of ectoderm tissue. The ectoderm is a type of germ cell layer present in a young embryo.
The central hollow tube of an artery is known as the arterial lumen. Lumen is the general term for the hollow part of any tubular structure.