Enter your Name:   Enter your E-mail Address:  Define the following terms: 01a. Ganglia 01b. Spinal nerves 01c. Efferent neurons 01d. Somatic motor nervous system 01e. Association neuron 01f. Excitability 02. Identify the parts of the neuron below: 03. How many axons does a multipolar neuron have? 04. What is the purpose of a non-ciliated ependymal cell? 05. A nerve sends a signal from the CNS to the smooth muscles of the intestine. Is this a part of the autonomic nervous system or the somatic nervous system? 06. What two conditions must be met for an axon to regenerate when severed? Do axons in the CNS regenerate when severed? 07. During depolarization in an axon, what is happending to the sodium ions? What is happening to the potassium ions? 08. The concentration of potassium ions outside an axon is very high, and the concentration of sodium ions inside is very high. Is the potential difference between the inside and outside of the axon negative or positive? 09. What has to happen to the axon in problem #8 in order to get back to the resting potential? 10. A stimulus on a neuron does not result in an action potential. There are two reasons why this might not happen. What are those reasons? 11. An action potential travels along an axon by skipping from node of Ranvier to node of Ranvier. What is this kind of conduction called? Is this faster or slower than an action potential running down an axon by continuous conduction? 12. You are listening to the radio. Suddenly, your little brother turns the radio up really loud, so that the noise actually hurts your ears. Compare the maximum potential difference of each individual action potential before and after your little brother turned the volume up. 13. In the situation described in problem #12, compare the frequency of action potentials running from your ears to your CNS before and after your little brother turned the volume up. 14. A signal is stimulated at a receptor and travels to the CNS. The number and frequency of action potentials is exactly the same at the CNS as it was at the receptor. Did this signal travel through a synapse? 15. A signal travels down an axon and then encounters an excitatory synapse. Comopare the frequency of action potentials in the presynaptic neuron and the postsynaptic neuron. 16. At a synapse, the release of neurotransmitters results in an opening of potassium channels at the postsynaptic membrane. Is this an inhibitory synapse or an excitatory synapse? 17. A signal originates in one receptor and ends up creating action potentials in many different places in the CNS and PNS. What kind of neuron arrangement did it pass through?