Reissner membrane seperates:
**Core Concept**
The Reissner membrane is a thin layer of cells that separates the endolymph-filled space of the membranous labyrinth from the perilymph-filled space of the scala vestibuli in the inner ear. It plays a crucial role in maintaining the endolymph composition and volume.
**Why the Correct Answer is Right**
The Reissner membrane is a specialized structure that separates the endolymph-filled scala media from the perilymph-filled scala vestibuli. It is composed of a single layer of flat, plate-like cells called the marginal cells, which are surrounded by a layer of pillar cells. The Reissner membrane is permeable to potassium ions, allowing for the movement of ions and water into the scala media, which is essential for maintaining the endolymph composition and volume. This unique structure allows for the generation of the endocochlear potential, which is essential for sound processing and hearing.
**Why Each Wrong Option is Incorrect**
**Option A:** is incorrect because it does not accurately describe the location of the Reissner membrane.
**Option B:** is incorrect because it confuses the Reissner membrane with another structure in the inner ear.
**Option C:** is incorrect because it is not the primary function of the Reissner membrane.
**Clinical Pearl / High-Yield Fact**
The Reissner membrane is a critical structure in the inner ear that plays a key role in maintaining the endolymph composition and volume. Damage to this membrane can lead to hearing loss and balance disorders.
**Correct Answer: C. Scala vestibuli and scala media.**