Neck Neck The neck is the part of the body, on many vertebrates, that separates the head from the torso. It contains blood vessels and nerves that supply structures in the head to the body. These in humans include part of the esophagus, the larynx, trachea, and thyroid gland, major blood vessels including the carotid arteries and jugular veins, and the top part of the spinal cord. In anatomy, the neck is also called by its Latin names, cervix or collum, although when used alone, in context, the word "cervix" more often refers to the uterine cervix, the neck of the
Drug delivery to the brain it "may reflect an influence of the astrocytes on the formation and the maintenance of the blood–brain barrier. The main function of the blood–brain barrier is to protect the brain and keep it isolated from harmful toxins that are potentially in the blood stream. It accomplishes this because of its structure, as is usual in the body that structure defines its function. The tight junctions between the endothelial cells prevent large molecules as well as many ions from passing between the junction spaces. This forces molecules to go through the endothelial cells in order to enter the brain tissue, meaning