The cells of the nervous system neurotransmitters at synapse

• What are the main structures of a neuron?

  Dendrites, cell body, and axon
• What is the function of the myelin sheath?

  Insulates axons and increases impulse speed
• When does myelination continue?

  From birth to adolescence
• What happens when diseases destroy the myelin sheath?

  Causes a loss of coordination
• What do glial cells produce?

  The myelin sheath
• What is the role of neurotransmitters at synapses?

  Facilitate chemical transmission
• What are the components involved in chemical transmission at the synapse?

  Vesicles, synaptic cleft, and receptors
• Why is it necessary to remove neurotransmitters?

  To prevent continuous stimulation of neurons
• How does the myelin sheath affect impulse conduction?

  It insulates the axon and increases speed
• How do responses to stimuli in infants compare to older children?

  They are not as rapid or coordinated
• Where do neurons connect with other neurons or muscle fibers?

  At the synaptic cleft
• What do neurotransmitters do at the synaptic cleft?

  Relay impulses across the cleft
• Where are neurotransmitters stored?

  In vesicles at axon endings
• What triggers the release of neurotransmitters?

  Arrival of an impulse
• How do neurotransmitters interact with postsynaptic neurons?

  They bind to receptors on the membrane
• What determines whether a signal is excitatory or inhibitory?

  The receptors on the postsynaptic neuron
• How can synapses filter out weak stimuli?

  By insufficient secretion of neurotransmitters
• What is required to transmit an impulse on the postsynaptic membrane?

  A minimum number of neurotransmitter molecules
• What is summation in the context of neurotransmission?

  Combining weak stimuli to trigger an impulse
• What do convergent neural pathways do?

  Release enough neurotransmitter to trigger an impulse
• What are endorphins?

  Neurotransmitters that reduce pain intensity
• When does endorphin production increase?

  During severe injury or prolonged exercise
• What feelings are linked to increased levels of endorphins?

  Feelings of pleasure from activities
• What is the function of dopamine?

  Induces feelings of pleasure and reinforces behavior
• What does the reward pathway involve?

  Neurons that secrete or respond to dopamine
• When is the reward pathway activated?

  When engaging in beneficial behaviors
• What types of drugs are used to treat neurotransmitter-related disorders?

  Agonists and antagonists
• What do agonists do at a synapse?

  Stimulate specific receptors mimicking neurotransmitters
• What do antagonists do at a synapse?

  Block the action of neurotransmitters
• How do some drugs enhance neurotransmitter effects?

  By inhibiting degradation or reuptake
• How do recreational drugs affect neurotransmission?

  Alter mood, cognition, perception, and behavior
• What causes drug addiction?

  Repeated use of drugs acting as antagonists
• What causes drug tolerance?


  Repeated use of drugs acting as agonists
• How do antagonists affect receptor sensitivity?

  Increase the number and sensitivity of receptors
• What is desensitization in the context of agonists?

  Decreased number and sensitivity of receptors
• What must individuals do to achieve the same effect with agonists over time?

  Take more of the drug