10.5 Speed of the nerve impulse

Factors Affecting Action Potential Speed

Myeline Sheath: This insulator prevents a potenital tarvelling along the whiole axon, meaning that it has to jump between nodes of ranvier. It increases the speed of the impulse by 60ms-1.

Diameter: In a larger axon there is less ion leakage, meaning that the impulse travels faster.

Temperature: As temperature gets higher, ions diffuse through the plasma membrane quicker. Also the enzymes required for respiration work faster, and the enzymes in the sodium-potassium pump work faster. Respiration is needed to povide energy for the pumps. If temperature gets too high then these enzymes will become…