Brainstem nuclei regulating sleep, arousal.

Ridge where palate halves meet.

The pharyngeal raphe is a raphe that serves as the posterior attachment for several of the pharyngeal constrictors (thyropharyngeal part of the inferior pharyngeal constrictor muscle, middle pharyngeal constrictor muscle, superior pharyngeal constrictor muscle).

Line dividing scrotum and anus.

Divides scrotum into symmetrical halves.

Fibrous band, connects jaw muscles.

Ridge underneath penis, seam-like.

Midline seam on scrotum exterior.