Breathe Easy: Master the 2026 Respiratory System Anatomy Challenge!

The lobes of the right lung are divided by two fissures: a horizontal fissure and an oblique fissure. The horizontal fissure runs across the lung to separate the upper (superior) lobe from the middle lobe. The oblique fissure runs obliquely from the hilum toward the lower border, separating the middle lobe from the lower (inferior) lobe. So the correct arrangement is that the horizontal fissure divides the upper and middle lobes, and the oblique fissure divides the middle and lower lobes. The idea that the horizontal fissure separates upper from lower, or that there’s only one fissure on the right, isn’t accurate.