Dendrites

Definition

Dendrites are tree-like extensions of neurons that receive signals from other nerve cells. They play a crucial role in transmitting information to the neuron’s cell body, integrating synaptic inputs, and determining the overall activity of the neuron. The structure of dendrites allows for a large surface area to form connections with many other neurons, which is essential for complex signaling in the nervous system.

5 Must Know Facts For Your Next Test

1. Dendrites have spines, which are small protrusions where synapses form, increasing the surface area for connections with other neurons.
2. The number and structure of dendrites can change over time in response to experience, a phenomenon known as synaptic plasticity.
3. Dendrites can receive thousands of inputs from other neurons, making them essential for processing and integrating information.
4. They help determine whether a neuron will fire an action potential based on the sum of excitatory and inhibitory signals received.
5. Dendritic dysfunction can be associated with various neurological disorders, including schizophrenia and autism.

Review Questions

• How do dendrites contribute to the overall functioning of a neuron?
  • Dendrites contribute to a neuron's function by receiving and integrating signals from multiple other neurons. They possess numerous synaptic connections that allow them to gather excitatory and inhibitory inputs, which are then summed up. If the cumulative signal reaches a certain threshold, it triggers an action potential in the neuron, leading to the transmission of information down the axon.
• Discuss the significance of dendritic spines in neural communication and their role in synaptic plasticity.
  • Dendritic spines are crucial for neural communication because they serve as sites for synaptic connections between neurons. Each spine can host a synapse where neurotransmitters bind, facilitating signal transmission. Additionally, dendritic spines are dynamic structures that can grow or shrink in response to learning and experience, reflecting synaptic plasticity—an important mechanism for memory formation and cognitive function.
• Evaluate how alterations in dendritic structure might influence neurological disorders and what this implies for therapeutic approaches.
  • Alterations in dendritic structure, such as changes in spine density or morphology, can significantly impact neuronal connectivity and function, potentially leading to neurological disorders like schizophrenia or autism. Understanding these changes provides insights into how these conditions might arise from altered neural circuits. This knowledge is critical for developing targeted therapeutic approaches aimed at restoring normal dendritic function or enhancing synaptic connections as a way to mitigate symptoms.

Related terms

Axon: An axon is a long, thin structure that transmits electrical impulses away from the neuron's cell body to other neurons or muscles.

Synapse: A synapse is the junction between two neurons where communication occurs through neurotransmitters released from the presynaptic neuron to bind to receptors on the postsynaptic neuron.

Neurotransmitter: Neurotransmitters are chemical messengers that transmit signals across a synapse from one neuron to another, playing a key role in communication within the nervous system.