In aging, decreased dark adaptation is due to cataracts and which rhodopsin-related change?

Prepare for the NBEO Human Development Exam with comprehensive quizzes and detailed explanations. Sharpen your understanding with multiple choice questions designed to mimic the real test. Get ready to succeed!

Multiple Choice

In aging, decreased dark adaptation is due to cataracts and which rhodopsin-related change?

Explanation:
Dark adaptation relies on rod vision and the regeneration of rhodopsin after it’s bleached by light. With aging, the process that forms rhodopsin can be reduced, so there are fewer rhodopsin molecules ready to respond in low-light conditions. This makes night vision slower and less sensitive, even when cataracts are present. Iodopsin is the cone pigment important for color and daylight vision, not the primary driver of dark adaptation, so changes in its formation don’t explain the decrease. Increased rhodopsin formation would actually enhance night vision, which isn’t observed here.

Dark adaptation relies on rod vision and the regeneration of rhodopsin after it’s bleached by light. With aging, the process that forms rhodopsin can be reduced, so there are fewer rhodopsin molecules ready to respond in low-light conditions. This makes night vision slower and less sensitive, even when cataracts are present. Iodopsin is the cone pigment important for color and daylight vision, not the primary driver of dark adaptation, so changes in its formation don’t explain the decrease. Increased rhodopsin formation would actually enhance night vision, which isn’t observed here.

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy