Where do the basal and alar plates abut laterally?

Where do the basal and alar plates abut laterally?

• A. At the sulcus limitan
• B. At the sulcus limitans
• C. At the central canal
• D. At the anterior median fissure

Answer: (A)

The boundary between the basal (ventral) and alar (dorsal) plates is the sulcus limitans. This longitudinal groove runs along the lateral wall of the neural tube and marks where the ventral motor region (basal plate) meets the dorsal sensory region (alar plate). The central canal is the internal cavity at the center, and the anterior median fissure is a ventral surface groove—neither marks the boundary between these two plates. The term sulcus limitan is simply a misspelling of sulcus limitans.

The boundary between the basal (ventral) and alar (dorsal) plates is the sulcus limitans. This longitudinal groove runs along the lateral wall of the neural tube and marks where the ventral motor region (basal plate) meets the dorsal sensory region (alar plate). The central canal is the internal cavity at the center, and the anterior median fissure is a ventral surface groove—neither marks the boundary between these two plates. The term sulcus limitan is simply a misspelling of sulcus limitans.