Sinapse Química: Animação | Anatomia e etc

Summary

The video explains the process of neuronal communication, detailing how neurons transmit signals through synapses. An action potential travels down the axon to the axon terminal, where neurotransmitters are released into the synaptic cleft. These chemicals affect the post-synaptic neuron by altering its charge distribution, leading to either an excitatory or inhibitory effect. The interaction of these signals determines whether a new action potential is generated. This intricate process is responsible for our thoughts and the coordination of all bodily activities, highlighting the complexity of neural networks in our brain.

Takeaways

• 😀 The brain constantly processes information by communicating through billions of nerve cells.
• 😀 Signals are passed from one neuron to another at a synapse, a junction between the neurons.
• 😀 An action potential in the pre-synaptic neuron travels down the axon to the axon terminal.
• 😀 The space between the pre-synaptic and post-synaptic neuron is called the synaptic cleft.
• 😀 Neurotransmitters in vesicles are released into the synaptic cleft when the action potential reaches the axon terminal.
• 😀 Calcium ions enter the axon terminal and trigger neurotransmitter release into the synaptic cleft.
• 😀 Neurotransmitters bind to receptors on the post-synaptic neuron, altering its electrical charge distribution.
• 😀 The binding of neurotransmitters to receptors opens ion channels, potentially generating a new action potential in the post-synaptic neuron.
• 😀 Excitatory signals make the post-synaptic neuron more likely to fire an action potential.
• 😀 Inhibitory signals make the post-synaptic neuron less likely to fire an action potential.
• 😀 The interaction of excitatory and inhibitory signals determines whether or not the post-synaptic neuron generates an action potential, coordinating thoughts and bodily activities.

Q & A

What is the primary function of synapses in the brain?

Synapses facilitate communication between neurons by passing signals from a presynaptic neuron to a postsynaptic neuron, enabling the processing of information in the brain.

What is the role of neurotransmitters in the process of synaptic transmission?

Neurotransmitters are chemicals released from vesicles in the presynaptic neuron. They travel across the synaptic gap and bind to receptors on the postsynaptic neuron, influencing its membrane potential.

What happens when an action potential reaches the axonal terminal?

When an action potential reaches the axonal terminal, it triggers the opening of calcium channels, allowing calcium ions to enter the terminal, which then causes vesicles containing neurotransmitters to fuse with the membrane.

How do neurotransmitters affect the postsynaptic neuron?

Neurotransmitters bind to receptors on the postsynaptic neuron, causing ion channels to open and altering the ion distribution across the membrane. This can lead to the generation or inhibition of a new action potential.

What is the role of calcium ions in synaptic transmission?

Calcium ions enter the presynaptic terminal when action potentials arrive, binding to synaptic vesicles and causing them to fuse with the membrane, releasing neurotransmitters into the synaptic gap.

What happens to neurotransmitters after they are released into the synaptic gap?

Neurotransmitters diffuse across the synaptic gap and bind to receptors on the postsynaptic neuron. They are quickly removed from the gap to cease their effect, ensuring precise control over neuronal signaling.

What is the difference between excitatory and inhibitory signals in neurons?

Excitatory signals make the postsynaptic neuron more likely to generate an action potential, while inhibitory signals make it less likely to do so. The combined effects of these signals determine whether an action potential will be initiated.

What is the effect of multiple synapses on a single neuron?

A single neuron can receive signals from many different neurons, both excitatory and inhibitory. The balance of these signals determines the neuron's overall activity and its likelihood of generating an action potential.

How does the balance between excitatory and inhibitory signals affect neuronal behavior?

If excitatory signals dominate, the postsynaptic neuron is more likely to generate an action potential. If inhibitory signals are stronger, the neuron is less likely to fire, resulting in a balanced or regulated response.

What role do ion channels play in action potential propagation?

Ion channels, particularly sodium and potassium channels, open and close during an action potential, allowing ions to flow in and out of the neuron. This movement of ions is essential for propagating the action potential along the axon.