Which statement best describes the role of Bruch's membrane?

Which statement best describes the role of Bruch's membrane?

• A. It acts as a sieve regulating the exchange of nutrients, oxygen, and waste between the choriocapillaris and RPE
• B. It helps stabilize the retina's structural integrity
• C. It absorbs stray light to reduce glare
• D. It produces photopigments for vision

Answer: (C)

Bruch's membrane mainly serves as a diffusion barrier between the retinal pigment epithelium and the choroid, regulating the exchange of nutrients, oxygen, and waste between these tissues. This selective sieve-like function keeps outer retinal metabolism in check and supports the health of the photoreceptors. As we age, Bruch's membrane can thicken and accumulate deposits, which impairs diffusion and is linked to diseases like age-related macular degeneration. Absorbing stray light to reduce glare isn’t a role of Bruch's membrane; that function comes from the pigment-rich RPE and photoreceptors, which contain melanin and light-absorbing compounds to minimize backscatter. Producing photopigments is a job of the photoreceptor cells themselves, not Bruch's membrane. While Bruch's membrane helps separate layers and supports their interaction, the broader mechanical stabilization of the retina involves other structures such as the vitreous, sclera, and the RPE-Bruch's membrane interface, not Bruch's membrane alone.

Bruch's membrane mainly serves as a diffusion barrier between the retinal pigment epithelium and the choroid, regulating the exchange of nutrients, oxygen, and waste between these tissues. This selective sieve-like function keeps outer retinal metabolism in check and supports the health of the photoreceptors. As we age, Bruch's membrane can thicken and accumulate deposits, which impairs diffusion and is linked to diseases like age-related macular degeneration.

Absorbing stray light to reduce glare isn’t a role of Bruch's membrane; that function comes from the pigment-rich RPE and photoreceptors, which contain melanin and light-absorbing compounds to minimize backscatter. Producing photopigments is a job of the photoreceptor cells themselves, not Bruch's membrane. While Bruch's membrane helps separate layers and supports their interaction, the broader mechanical stabilization of the retina involves other structures such as the vitreous, sclera, and the RPE-Bruch's membrane interface, not Bruch's membrane alone.