Physiological Properties of Nerve Fibres

In this article we will discuss about physiological properties of nerve fibres.

What Are Nerve Fibres?

The component of a nerve cell (neuron) known as the axon, also known as a nerve fibre, is responsible for carrying nerve impulses away from the cell body. Typically, a neuron contains one axon that connects it to other neurons, muscle cells, or glandular cells. Some axons may extend all the way from the spinal cord to the tip of a toe.

Properties Of Nerve Fibres

i) Excitability

The nerve fibre shows a change in electrical activity from its resting state when a stimulus is applied.

ii) Conductivity

It is the capacity of the nerve fibre to transmit impulses along the entire length of the axon without causing any change in the action potential’s amplitude. The term “decrementless conduction” refers to this type of conduction.

iii) Refractory period

It is the duration after an effective stimulus, when a second stimulus is applied, there will be no response for the second stimulus.

physiological properties of nerve fibres

Excitability of the nerve fiber during absolute and relative refractory periods

a. From the time of the application of the stimulus till the initial one-third of the repolarization phase, the nerve fiber excitability will be zero and is completely refractory for the second stimulus. This duration is known as absolute refractory period.

b. Relative refractory period is the duration after an effective stimulus, when a second stimulus, which is slightly above threshold, is applied there will be response for the second stimulus as well.

iv) All or none law

According to this, the tissue will respond to stimuli of threshold or greater strength with the same amplitude as before, but will not respond to stimuli of threshold strength or less.

a. A single nerve fiber.

b. A single skeletal muscle fiber.

c. A motor unit.

d. Whole of cardiac muscle.

c. A single fiber of multi-unit smooth muscle.

d. Whole of visceral smooth muscle.