Briefly state the importance of voltage-gated Na+ channels. Explain why the tetrodotoxin (TTX) found in California newts (Tarichatorosa) does not kill the newts
Would you expect garter snakes (Thamnopissirtalis), which are predators of newts, to die once they consume the toxic newts?
What will be an ideal response?
Answer: Voltage-gated Na+ channels are important for the depolarizing phase of an action potential and thus for transmission of electrical signals. California newts, which contain the toxin TTX (TTX blocks voltage-gated sodium channels) have a mutation in one of the voltage-gated Na+ channels that does not allow the TTX to bind, and therefore, the newt is immune to the toxin. If garter snakes consume TTX-containing newts without dying, then these garter snakes must also have mutations that make their voltage-gated Na+ channels insensitive to TTX. Garter snakes and other predators without the mutation would most likely die if they consumed the toxic newts.
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