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
Blood–brain barrier was observed between adult and newborn rabbits. These experiments indicate that the newborn BBB has restrictive properties similar to that of the adult. In contrast to suggestions of an immature barrier in young animals, these studies indicate that a sophisticated, selective BBB is operative at birth. The blood–brain barrier acts effectively to protect the brain from circulating pathogens. Accordingly, blood-borne infections of the brain are rare. Infections of the brain that do occur are often difficult to treat. Antibodies are too large to cross the blood–brain barrier, and only certain antibiotics are able to pass. In some cases, a drug