Final answer:
Nerve impulse speed is influenced by the axon diameter and myelin sheath presence; the time taken for a signal to travel 1.1 meters at 18 m/s is approximately 0.0611 seconds. The maximum firing rate is then calculated as the inverse of this duration. Specific neuron adaptations like myelination enhance impulse transmission.
Step-by-step explanation:
The speed of propagation of an action potential or nerve impulse in a neuron is determined by several factors. One key factor is the diameter of the axon; larger diameters tend to allow faster transmission speeds. In addition, the presence of a myelin sheath can greatly increase propagation speed. If we know the length of the neuron is 1.1 meters and the speed of the nerve impulse is 18 m/s, we can calculate the time it takes for the nerve signal to travel the distance by dividing the length by the speed: Time = Distance / Speed = 1.1 m / 18 m/s ≈ 0.0611 seconds.
When determining the maximum firing rate of a nerve, we assume that one nerve impulse must end before another begins. The firing rate is the inverse of the time it takes for one impulse to occur. If an impulse takes 0.0611 seconds, then the maximum firing rate is 1 / 0.0611 s ≈ 16.37 impulses per second.
Morphological adaptations of neurons include the presence of a myelin sheath and larger axon diameters, both of which enhance the transmission speed of nerve impulses. The myelin sheath allows for saltatory conduction, where the nerve impulse jumps from one node of Ranvier to the next, greatly speeding up the impulse. These features make neurons highly suited for the rapid transmission of nerve impulses to other neurons, muscles, or glands.