Foramen magnum - Wikipedia, the free encyclopedia (240 words) |
 | In anatomy, in the occipital bone, the foramen magnum (Latin: 'great hole') is one of the several oval or circular apertures in the base of the skull (the foramina), through which the medulla oblongata (an extension of the spinal cord) enters and exits the skull vault. |
 | Apart from the transmission of the medulla oblongata and its membranes, the foramen magnum transmits the accessory nerve (the eleventh of the twelve cranial nerves), the vertebral arteries, the anterior and posterior spinal arteries, the membrana tectoria and alar ligaments. |
 | Comparisons of the position of the foramen magnum in early hominid species are useful to determine how comfortable a particular species was when walking on two limbs (bipedality) rather than four. |
Mandibular nerve - Wikipedia, the free encyclopedia (422 words) |
 | Mandibular division of trifacial nerve, seen from the middle line. |
 | It exits the cranial fossa (at the base of the skull) through the foramen ovale. |
 | It runs into the mandible via the mandibular foramen where it becomes the inferior alveolar nerve. |