Describe the main chemical events at a synapse. What will be ...

[Jramos095]

Describe the main chemical events at a synapse.
 
  What will be an ideal response?

Question 2

Sildenafil (Viagra) works by ____.
 
  a. increasing sensitivity to female's pheromones
  b. increasing release of nitric oxide in the hypothalamus and penis
  c. decreasing dopamine release in the hypothalamus
 d. blocking pain receptors in the spinal cord

[katheyjon]

Answer to Question 1

Understanding the chemical events at a synapse is fundamental to understanding the nervous system. Every year, researchers discover more and more details about synapses, their structure, and how those structures relate to function. Here are the major events:
1 . The neuron synthesizes chemicals that serve as neurotransmitters. It synthesizes the smaller neurotransmitters in the axon terminals and synthesizes neuropeptides in the cell body.
2 . Action potentials travel down the axon. At the presynaptic terminal, an action potential enables calcium to enter the cell. Calcium releases neurotransmitters from the terminals and into the synaptic cleft, the space between the presynaptic and postsynaptic neurons.
3 . The released molecules diffuse across the cleft, attach to receptors, and alter the activity of the postsynaptic neuron.
4 . The neurotransmitter molecules separate from their receptors.
5 . The neurotransmitter molecules may be taken back into the presynaptic neuron for recycling or they may diffuse away.
6 . Some postsynaptic cells send reverse messages to control the further release of neurotransmitter by presynaptic cells.

Answer to Question 2

b