Transmission of Information within Neurons:

 

 

Transmission of Information within Neurons:

1. Receptor Activation:
• Sensory receptors, specialized structures in the body (such as in the skin for touch or the retina in the eyes for light), respond to external stimuli. When a stimulus, like heat, light, or pressure, is detected, these receptors are activated.
2. Chemical Reaction and Electrical Impulse:
• When a receptor is activated, it sets off a series of events. The receptor generates a chemical reaction within its own cell. This reaction typically involves the movement of ions, such as sodium and potassium, across the cell membrane.
• The chemical reaction leads to a change in the electrical potential (voltage) of the receptor cell. This change in voltage generates an electrical impulse, known as an action potential, at the dendritic tip of the nerve cell. This is the starting point for the transmission of information.
3. Propagation Along the Neuron:
• The electrical impulse, in the form of an action potential, travels along the dendrite toward the cell body (soma) of the neuron. The cell body contains the nucleus and other organelles necessary for the maintenance and function of the neuron.
4. Axonal Transmission:
• From the cell body, the electrical impulse continues its journey along the axon, which is a long, thin extension of the neuron. The axon is insulated by a fatty substance called myelin, which helps speed up the transmission of the impulse.
• The impulse travels along the axon like an electrical signal traveling through a wire. It moves in one direction, away from the cell body and toward the endpoint of the axon.
5. Release of Neurotransmitters:
• Upon reaching the endpoint of the axon, known as the axon terminal or synaptic terminal, the electrical impulse triggers the release of certain chemicals called neurotransmitters. These neurotransmitters are stored in vesicles within the axon terminal.
6. Crossing the Synapse:
• The synaptic terminal of one neuron is separated from the dendrite of the next neuron by a tiny gap called a synapse. When the electrical impulse reaches the synapse, it cannot jump the gap itself.
• Instead, the neurotransmitters are released from the vesicles into the synapse. These neurotransmitters diffuse across the synapse, effectively bridging the gap between the two neurons.
7. Stimulating the Next Neuron:
• On the dendrite of the neighboring neuron (the postsynaptic neuron), there are specialized receptor molecules that can bind with the neurotransmitters released by the first neuron.
• When neurotransmitters bind to these receptors on the postsynaptic neuron, they initiate a chemical reaction within the second neuron, which generates a new electrical impulse in the dendrite of that neuron.
8. Continuation of the Impulse:
• This newly generated electrical impulse in the postsynaptic neuron then continues its journey, repeating the process. It travels along the dendrite, through the cell body, and down the axon, transmitting the signal to the next neuron or target tissue, such as a muscle cell or gland.

The transmission of nervous impulses within the body relies on the generation of electrical impulses at the dendritic tip of a nerve cell, their propagation along the neuron, the release of neurotransmitters at the axon terminal, and the subsequent initiation of electrical impulses in the next neuron. This process ensures the swift and efficient communication of information throughout the nervous system, allowing for rapid responses to sensory input and coordination of bodily functions.