Neurones and Synaptic Transmission

• How do neurons transmit signals?

  Neurons transmit signals electrically and chemically
• What is the function of dendrites in a neuron?

  Dendrites receive information from other neurons
• How do neurons transmit signals within the nervous system?

  Neurons transmit signals electrically and chemically.
• What is the role of dendrites in a neuron?

  Dendrites receive information from other neurons and send nerve impulses towards the cell body.
• What is the function of the axon in a neuron?

  The axon carries nerve impulses away from the cell body.
• What is the purpose of the myelin sheath?

  The myelin sheath insulates and protects the axon and helps speed up electrical transmission.
• What are the nodes of Ranvier?

  They are gaps in the myelin sheath that force the impulse to jump across the gaps along the axon.
• What do terminal buttons do?

  Terminal buttons send impulses to the next neuron across the synapse.
• What is the synapse?

  The synapse is the gap between one neuron and the next neuron.
• How do receptors function in the nervous system?

  Receptors detect changes in the environment from a stimulus and produce electrical impulses in response.
• What is a reflex action?

  A reflex action is an automatic involuntary response to a stimulus.
• What is the role of sensory neurons?

  Sensory neurons carry messages from the peripheral nervous system to the central nervous system.
• What is the function of motor neurons?

  Motor neurons carry nerve impulses from the central nervous system to effectors such as muscles and glands.
• Where are relay neurons found and what is their function?

  Relay neurons are found in the brain and spinal cord and carry nerve impulses between neurons, connecting sensory and motor neurons.
• How does a sensory neuron respond to a stimulus?

  A sensory neuron sends an electrical impulse to a relay neuron located in the spinal cord.
• What is synaptic transmission?

  Synaptic transmission is the process by which neighboring neurons communicate by sending chemical messages across the synapse.
• What triggers the release of neurotransmitters?

  The electrical impulse that has traveled down the axon triggers the release of neurotransmitters.
• What happens to neurotransmitters after they are released into the synapse?

  Neurotransmitters diffuse across the synapse and are received by receptors on the dendrites of the next neuron.
• What is the role of enzymes in synaptic transmission?

  Enzymes are released to break down any neurotransmitters still in the synapse.
• What is reuptake in the context of neurotransmitters?

  Reuptake is the process where excess neurotransmitters are reabsorbed back to the pre-synaptic terminal.
• What does summation refer to in neuronal communication?

  Summation refers to the total effect of excitatory and inhibitory influences on the post-synaptic neuron.
• How do excitatory neurotransmitters affect the likelihood of a neuron firing?

  Excitatory neurotransmitters increase the positive charge of the post-synaptic neuron, making it more likely to fire.
• What is the effect of inhibitory neurotransmitters on a neuron?

  Inhibitory neurotransmitters increase the negative charge of the post-synaptic neuron, making it less likely to fire.
• How does the total effect of neurotransmitters influence neuronal firing?

  If the total effect is inhibitory, the neuron is less likely to fire; if it is excitatory, the neuron is more likely to fire.
• What are the steps involved in synaptic transmission?Impulse reaches the pre-synaptic terminal.