Figure Q2-42 shows a patch clamp recording from the Shaker channel (ShB). What is the presumed molecular mechanism for inactivation of the channel? Figure Q2-42 A) Several positively charged amino acids in S4 B) Several negatively charge amino acids in S4 C) The N-terminal 'ball-and-chain' D) A block by Na⁺ ions

Question

Quizplus · Accepted Answer

The ball-and-chain is a specific string of amino acids that blocks the open channel. The charges in the S4 region give the channel its voltage sensitivity. The K⁺ channel is not blocked by Na⁺ in normal circumstances.

Figure Q2-42 Shows a Patch Clamp Recording from the Shaker