what effect does the diameter of conduction fibers have on the conduction of the heart?

Answer 1

You must be knowing that there are some factors that affect the velocity of conduction of impulse and diameter is one of them.
So, greater the diameter of the conduction fibres greater is the velocity of the impulse that travels along it. Conversely, lesser the diameter, lesser the velocity.The rate of impulse is proportional to the heart beat.

Answer 2

When the impulses reach these fibers they trigger the muscle fibers in the ventricles to contract.

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