QUESTION: Dendrite functions in neuron
ANS: Dendrites are branching extensions that project from the cell body of a neuron, resembling the branches of a tree. It performs following functions
- Dendrites are highly branched structures that serve as the main sites for receiving input from other neurons.
- Dendrites have specific patterns of branching and connectivity, allowing them to receive input from specific neurons and form synaptic connections.
- They contain numerous specialized structures called dendritic spines, which receive and process incoming signals.
- Dendrites receive synaptic inputs in the form of chemical signals called neurotransmitters released by neighboring neurons. These signals are detected by receptors on the dendritic spines.
- The signals received by dendrites from multiple synapses are integrated or summed up to determine whether the neuron will generate an electrical signal known as an action potential.
- When a dendrite receives a signal, the electrical potential of the neuron changes. This change in potential, known as a graded potential, spreads from the dendrites towards the cell body.
- If the graded potential is strong enough and reaches the threshold level, it can trigger the generation of an action potential, an electrical impulse that travels along the neuron’s axon for further transmission.
| Function of Dendrites in Neurons | Interesting Facts |
| Receiving Incoming Signals | · Dendrites are covered in tiny structures called dendritic spines
· Dendritic spines increase the surface area for receiving signals and allow for a greater number of synaptic connections. · Dendritic spines can undergo structural changes in response to neural activity and experiences · They also contribute to synaptic plasticity and learning. |
| Signal Integration | · Dendrites integrate inputs from thousands of synapses
· Weighing the incoming signals to determine whether the neuron will generate an action potential or not · Recent studies have shown that dendrites possess computational capabilities, actively processing and shaping information before it reaches the cell body. |
| Transferring Signals | · Electrical signals (graded potentials) generated in dendrites propagate toward the cell body, initiating electrical activity within the neuron.
· Dendrites can exhibit active properties, such as the generation of dendritic spikes, which contribute to the amplification and propagation of signals. |
| Connectivity
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· Dendritic morphology and connectivity patterns are unique to different types of neurons, enabling them to receive specific inputs and participate in specialized neural circuits.
· Dendrites can undergo structural changes in response to synaptic activity, such as · Sprouting of new branches · Retraction of existing branches |