What Are Nerve Cells?

Nerve cells, also known as neurons, are specialized cells that convey information within the nervous system. Neurons play a critical role in transmitting signals between different parts of the body and the brain. Here’s how they function:

Structure of a Neuron:

1. Cell Body (Soma): Contains the nucleus and most of the cell’s organelles. It is responsible for maintaining the cell’s health and integrating incoming signals.
2. Dendrites: Branch-like structures that receive signals from other neurons and transmit them to the cell body.
3. Axon: A long, slender projection that carries signals away from the cell body to other neurons, muscles, or glands.
4. Myelin Sheath: A fatty layer that insulates the axon, speeding up signal transmission.
5. Axon Terminals: The endpoints of the axon where signals are transmitted to other neurons or target cells via synapses.

Types of Neurons:

1. Sensory Neurons: Transmit sensory information (e.g., touch, sound, light) from receptors to the central nervous system (CNS).
2. Motor Neurons: Carry instructions from the CNS to muscles or glands, enabling movement and other actions.
3. Interneurons: Found in the CNS, they connect sensory and motor neurons and are involved in complex processes like reflexes and higher cognitive functions.

How Neurons Convey Information:

1. Electrical Signals: Neurons generate electrical impulses called action potentials. These travel along the axon to the axon terminals.
2. Chemical Signals: At the synapse, the electrical signal triggers the release of neurotransmitters, which are chemical messengers that cross the synaptic gap to the next neuron or target cell.
3. Signal Processing: The receiving neuron processes the chemical signal, which may excite or inhibit it from generating its own action potential.

Importance of Neurons:

Neurons form the foundation of the nervous system, enabling vital functions like:

• Reflex actions.
• Voluntary movements.
• Sensory perception.
• Thought, memory, and emotion.

Damage or dysfunction in neurons can lead to neurological disorders such as Alzheimer’s, Parkinson’s, or multiple sclerosis, underscoring their critical role in overall health and function.