Body electric signals assignment

2. Describe the structure of a neuron.

3. Distinguish between a neuron and a glial cell. Use this image of an action potential to answer the following questions.

4. What happens to the membrane potential after 5 ms?

5. At the peak point when the membrane potential is 40mV does the cell have an overall negative charge or positive charge?

6. Hyperpolarization which means the cell becomes more negatively charged than it is at resting potential (more negative than -70 mV)can happen as a result of the binding of an inhibitory neurotransmitter to its receptor. Propose what happens to sodium and potassium ions during hyperpolarization.

7. How does voltage relate to the membrane potential?

8. What would happen to a cell if its sodium and potassium pumps failed to work at the end of an action potential?

9. The backflow of a nerve impulse is prevented by the fact that at a chemical synapse the axon terminal does not have neurotransmitter receptors and dendrites cannot secrete neurotransmitter chemicals. What does this statement tell you about the direction of nerve impulses in neurons?

10. Identify two types of synapses in the nervous system.

11. What is the purpose of the digestive enzymes found in the synaptic cleft?

12. Distinguish a neurotransmitter from a hormone.

13. What is the major function of the central nervous system?

14. Outline the major functions of the cerebral cortex. Use this image of the lobes of the brain to answer the following questions.

15. What is the name of the blue structure?

16. Identify a sense that is interpreted in the yellow-colored lobe (center left) and name that lobe.

17. Identify the two main divisions of the peripheral nervous system and describe their roles in the body.

18. What are the two divisions of the autonomic nervous system?

19. Distinguish between the sympathetic and parasympathetic nervous systems.

20. What type of sensory receptors are found in the eyes?

21. Distinguish between rods and cones.

21. Why are taste and smell called the “two chemical senses”? 22. Outline how the ear is important to the sense of body balance.

23. What role does skin have in detecting external stimuli?

24. What kind of effects should a drug have for it to be called psychoactive?

25. Identify the main effect of psychoactive drugs on the CNS. 26. How do the effects of a stimulant differ from the effects of a depressant?

27. What is the brain reward system and how is it affected by an addictive drug?

28. How does cocaine affect the brain reward system? Use this graph that shows the differences in blood concentration of nicotine over time to answer the following questions.

29. Review the graph that illustrates the increases in blood-nicotine concentrations from four different forms of tobacco; Cigarettes oral snuff chewing tobacco and nicotine gum. Which of the four forms of nicotine increases blood-nicotine concentration the fastest?

30. Which of the four forms of nicotine increases blood-nicotine concentration the least?

31. Can you tell from this graph whether one form of tobacco is safer than another? Requirements: normal ‘