Chapter 12 - Nervous System
The glossy-white appearance of most axons is due to Question 9 options: A) the white color of the perivascular feet. B) their proximity to light-reflecting cartilage. C) the high lipid content of the myelin sheath. D) the covering of ependymal cells. E) their proximity to white bone.
C
The portion of the nervous system that has voluntary control over skeletal muscles is the ________ division. Question 13 options: A) autonomic motor B) somatic sensory C) somatic motor D) visceral sensory
C
A mixed nerve is one that contains both Question 1 options: A) an endoneurium and an epineurium. B) sensory and motor neurons. C) presynaptic and postsynaptic neurons. D) cranial and spinal nerve fibers. E) unipolar and bipolar neurons.
B
Action potentials are generated by the opening of ________ gated channels and they occur on the ________. Question 4 options: A) chemically, dendrite B) voltage-, axon C) voltage-, dendrite D) chemically, axon
B
Nerves and ganglia are structures found in the Question 14 options: A) central and peripheral nervous systems. B) peripheral nervous system. C) central nervous system.
B
The glial cell that helps to circulate cerebrospinal fluid is the Question 15 options: A) astrocyte. B) ependymal cell. C) neurolemmocyte. D) microglial cell. E) oligodendrocyte.
B
The portion of the nervous system that conducts impulses from the skin, joints, skeletal muscles, and special senses is the ________ division. Question 5 options: A) autonomic motor B) somatic sensory C) somatic motor D) visceral sensory
B
Based on structure, the most common type of neuron is the ________ neuron. Question 12 options: A) unipolar B) bipolar C) multipolar D) pseudounipolar
C
Conductive activity in a neuron generally causes it to secrete Question 7 options: A) a specific neurotransmitter that always excites its target. B) several types of neurotransmitters simultaneously, that are broadcast to excite and inhibit multiple targets. C) a specific neurotransmitter that either excites or inhibits its target. D) several types of neurotransmitters simultaneously, that all work to prevent another immediate impulse. E) several types of neurotransmitters simultaneously, all of which excite the cell's target.
C
The nervous system controls the activity of muscles and glands. Muscles and glands can generate changes and are therefore called Question 3 options: A) afferents. B) visceral. C) stimuli. D) effectors.
D
A graded potential is one that Question 6 options: A) varies in size depending on the magnitude of the stimulus (larger voltage change for stronger stimulus). B) is all or none (always the same intensity). C) travels the length of the nerve fiber (is long-distance). D) lasts for several seconds after ion channels have opened, closed, and reset.
A
Receptors are parts of the nervous system that allow it to Question 11 options: A) collect information. B) conduct impulses to muscles. C) initiate responses to information. D) process information.
A
When multiple presynaptic neurons release neurotransmitter at various locations onto the postsynaptic neuron at the same time, this results in Question 10 options: A) spatial summation. B) suprathreshold hyperpolarization. C) several action potentials. D) temporal summation.
A
Which is not a general function of the nervous system? Question 8 options: A) Transporting materials throughout the body B) Processing and evaluating information C) Collecting information D) Responding to information E) No exceptions; all are general functions of the nervous system.
A
When voltage-gated K+ channels open on the conductive segment of a neuron, Question 2 options: A) potassium enters, depolarizing the cell to a positive value. B) potassium enters, repolarizing the cell to a negative value. C) potassium exits, depolarizing the cell to an even more negative value. D) potassium exits, repolarizing the cell to a negative value. E) potassium enters, repolarizing the cell to a positive value.
D
