Which value reflects the number of semicircular canals in the inner ear?

Which value reflects the number of semicircular canals in the inner ear?

• A. Two
• B. Three
• C. Four
• D. Five

Answer: (B)

The inner ear has three semicircular canals, arranged in three perpendicular planes to detect rotational movement of the head in any direction: the horizontal (lateral), anterior (superior), and posterior canals. This trio enables sensing angular acceleration across all axes. Each canal contains hair cells in the crista ampullaris that respond to fluid movement as the head turns. Because there are three canals, the value reflecting the number is three. The other numbers listed don’t fit the actual anatomy of the inner ear. Thus, three is the correct value.

The inner ear has three semicircular canals, arranged in three perpendicular planes to detect rotational movement of the head in any direction: the horizontal (lateral), anterior (superior), and posterior canals. This trio enables sensing angular acceleration across all axes. Each canal contains hair cells in the crista ampullaris that respond to fluid movement as the head turns. Because there are three canals, the value reflecting the number is three. The other numbers listed don’t fit the actual anatomy of the inner ear. Thus, three is the correct value.