Consider Visual Transduction in Rod Photoreceptors in the Vertebrate Retina

question 42

Multiple Choice

Consider visual transduction in rod photoreceptors in the vertebrate retina. Which of the following steps does NOT normally amplify the signal in this pathway?

• A) Activation of transducin by active rhodopsin
• B) Blockage of Na⁺ influx by cation-channel closure
• C) Cation-channel closure due to cGMP depletion
• D) Depletion of cGMP by active cGMP phosphodiesterase
• E) All of the above DO involve amplification

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Net Present Value; a financial metric used to assess the profitability of an investment by calculating the difference between the present value of cash inflows and outflows associated with the investment.

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