Question

1. The effect of a neurotransmitter on a postsynaptic neuron are typically very brief because the concentration of the neurotransmitter in the synaptic cleft decreases rapidly soon after transmitter is secreted by the presynaptic neuron. Describe 3 mechanisms by which the transmitter is removed.
2. Which of the following characteristics does NOT apply to both chemical and electrical synapses?
   1. Communication between interacting cells involves changes ion concentrations in the cytosol
   2. Only one-way communication between nerve cells is permitted.
   3. Action potentials are involved with communication between nerve cells.
   4. None of these apply to both type of synapses
3. Which of the following changes will induce an IPSP in a postsynaptic neuron?
   1. Influx of calcium ions
   2. Efflux of potassium ions
   3. Efflux of chloride ions
   4. Influx of sodium ions
4. An increase in carbon dioxide levels in the cerebral spinal fluid will cause respiration rate to?
   1. Increase
   2. Remain the same
   3. Decrease
5. As the strength of a stimulus increases, the amplitude of a receptor potential?
   1. Decreases
   2. Remain the same
   3. Increases
6. Briefly explain how an increase in cerebrospinal fluid concentrations of carbon dioxide results in action potential of pH receptors in the…
7. An increase in Oxygen levels in arterial blood will cause respiration rate to:
   1. Remain the same
   2. Decrease
   3. Increase
8. Briefly describe two major differences between the dorsal column-medial lemnisci and anterolateral systems.
9. Which of the following effects in a postsynaptic neuron is a likely effect mediated by a metabotropic receptor?
   1. None of these
   2. Increased transcription of genes for ion channels
   3. Increased transcriptions of genes for enzymes involved with the production of intracellular messengers
   4. All of these
   5. Increased transcription of genes for ionotropic receptors

Answer 1

1) The answer is d) because the options given in the question are apply to both of the synapses.

2) The inhibitory postsynaptic is a temporary hyperpolarization of the post synaptic membrane caused by the flow of negatively charged ions in to the post synaptic cell.

So the answer is efflux of chlorine ions

3) An increase in carbondioxide in cerebrospinal fluid leads to increase demands of oxygen causing the respiratory rate and volume to increase

The answer is a) increase the respiration rate

4) The strength of stimulus is increase , the amplitude of receptor potential is also increase .

The answer is c) increase