Reflexes Uncovered-Pathway of an action potential Comprehensive Paper - Essay Example

A stimulus is generated immediately a person comes in contact with a painful object like fire. The stimulus has to pass through layers of the layers of the skin, which include the epidermis and the dermis. The anatomy of the skin displays a rich network of receptors that are responsible for detecting pain (Moses et al., 67). The epidermis consists of hair and Merkel’s disc, which is a tactile receptor found between the epidermis and the dermis. This receptor detects any form of external stimuli.

The Pacinian corpuscle is also found in the outermost layer of the skin and it detects abnormal pressures from external environment. Apart from these receptors, the outer skin layer has free nerve endings that detect pain. The stimulus goes through the free nerve endings to other sensory receptors in the dermis (Moses et al., 70). The presence of sensory receptors enables the skin to detect any change in environmental pressures like fire. The dermis also has the Ruffini’s corpuscle which is a receptor similar to a mushroom shape.

The stimulus is also detected by the Pacinian corpuscle, which detects deep pressure within the hypodermis layer. The dermis contains free nerve endings that play a major part in detecting external stimuli. A stimulus excites the impulse at the resting membrane potential of the neuron threshold potential in order to reach the maximum action potential. When the maximum action potential is achieved, the cell membrane of the neurons becomes depolarized and the sensory receptors convert the portrayed information into nerve impulses.

As a result the nerve impulse away from the dendrites into the neuron then onto the cell body of the nerve. It then travels via the myelin sheath of the axon, to the nodes of Ranvier and lastly to the synaptic knob where the axon and another neuron meet each other. The gap between one neuron and another is called the presynaptic membrane