Worksheet for Nervous Systems
Biology 100C
1. What are the three main functions of a nervous system?
2. What structures comprise the Central Nervous System (CNS)?
3. Motor output is the conduction of signals from the _____________ to the _____ _________.
4. Signals are conducted by ____ _____________ which are bundles of _____ _______ wrapped in connective tissue.
5. Sensory and motor neurons are collectively called the ______
6. The structural and functional unit of the nervous system is the _________ ____________.
7. What are the four main parts of a neuron?
8. The site of contact between a synaptic terminal of a neuron and a target, such as another neuron, a muscle cell, or a gland, is called a ______ ____________________.
9. What are the cells called that lie on each side of a synapse?
10. The simplest type of nerve circuit is termed a ______ _________________.
11. What is the minimum number of neurons that can make up a “reflex arc”, and what would these neurons be?
12. What are “interneurons”?
13. Interneurons are constantly __ ___. What does this active provide the context for?
14. Ganglia and nuclei are collections of ______ ______. How do they differ from one another?
15. Supporting cells, called ______ __________ are ____ _____.
16. Which glial cells provide structural and metabolic support for neurons?
17. What do these glial cells also form?
18. What cells form the insulating sheaths around axons? Where are these cells found?
19. All cells have an electrical charge difference across their plasma membrane called the ____ _____________________________________.
20. The membrane potential exists because:
21. The membrane potential of an unstimulated neuron is called the ____ ________________________.
22. What makes invertebrates like squid and lobsters such good animals for the study of nerve impulses?
they are large in diameter
23. What is the principal + charged ion outside of a cell?
24. What is the principal + charged ion inside of a cell?
25. How do these ions move across the cell membrane?
26. All cells have a membrane potential; however, only certain cells such as __ __________ and ____ _________ have the ability to generate large changes in their membrane potential. These cells are called _____ _________________________.
27. What types of ion channels are present in the cell membrane? How are these channels opened?
28. What are the two different types of “graded potentials”?
29. Define each type of “graded potential”. Tell which ion channel is involved in each type of “graded potential”.
30. Why are these voltage changes called “graded potentials”?
31. If a sufficiently strong stimulus causes depolarization to reach “threshold potential” it triggers a different type of response called an _____ ________.
32. In a neuron, an action potential can only be generated in the ____ _________________.
33. The action potential is a non-graded, all or non event; meaning ___
34. The action potential arises because the plasma membrane has ___ ____ ion channels.
35. Which two types of voltage-gated ion channels contribute to the action potential?
36. Which voltage-gated ion channel opens first and which one opens second in an action potential?
37. The _____ _, not their amplitude, codes for stimulus intensity in the nervous system.
38. What two factors affect the speed at which an action potential travels down an axon?
39. What is a synapse?
40. Name the two general types of synapses.
41. One important function of the chemical synapse is to allow __ _.
42. The “motor division” of the peripheral nervous system is divided into two functional divisions, called the ___ ___________________ and ______ _________________ nervous systems.
43. The somatic nervous system carries signals to _____ ____.
44. The autonomic nervous system carries signals to ___
45. The autonomic nervous system consists of two divisions that act on body organs with ___ ____________________________.
46. The Sympathetic Division correlates with ______
47. The Parasympathetic Division causes ___ _________________________________.