VII. Nervous system questions
Nervous system questions
There are a total of 16 nervous system questions, which are important content-oriented in the summary part of this chapter. Click the ‘Answer’ button to see the corresponding answers and explanations, and click the ‘Go back’ button to slove the next questions.
1. Action potential is generated when _____________ enters into the neuron and then _____________ flows outward.
A. Na+, K+
B. Na+, Cl–
C. Ca+, Na+
D. Na+, Ca+
E. K+, Na+
2. Which of the following is the correct order of response of the nervous system to stimulus?
- Afferent → Interneuron → Efferent → Response
- Efferent → Interneuron → Afferent → Response
- Interneuron → Afferent → Efferent → Response
- Response → Efferent → Afferent → Interneuron
- None of the above
3. Acetylcholine is broken down at the site of _______________ .
A. Synaptic vesicles
B. Voltage-gated Ca2+ channels
C. Presynaptic membranes
D. Postsynaptic membranes
E. C and D
4. Sympathetic division can cause all of the symptoms below EXCEPT _______________.
A. Increasing rates of glycogen to glucose conversion
B. Accelerating heart rate
C. Stimulation of the adrenal medulla
D. Stimulation of the gallbladder
E. Dilation of the pupil of the eye
5. The neurotransmitter of norepinephrine is _______________ .
A. Released by preganglionic neurons in the parasympathetic nervous system.
B. Released by postganglionic neurons in the parasympathetic nervous system.
C. Released by preganglionic neurons in the sympathetic nervous system.
D. Released by postganglionic neurons in the sympathetic nervous system.
E. A sympathetic chain between preganglionic neurons and postganglionic neurons.
6. Acetylcholine is a neurotransmitter, an important intercellular chemical messenger. How does it affect the generation of action potential on the postsynaptic membrane?
Ⅰ. By binding ligand-gated ion channels, it opens cation channels. |
A. I only
B. I and II
C. I, II, and III
D. II, III, and IV
E. All of the above
7. Neurons are composed of following EXCEPT _____________.
A. Axons
B. Dendrites
C. Cell bodies
D. Action potential
E. Myelin sheath
8. Before extracting a tooth, dentists anesthetize the area around the tooth, which becomes numb. This is explained as follows:
A. Anesthetic blocks the opening of voltage-gated Na+ channels to hinder generation action potential.
B. Anesthetic stops making the synaptic vesicles to hinder the transport of neurotransmitters.
C. Anesthetic disturbs the opening of voltage-gated Ca2+ channels to hinder the release of neurotransmitters into the synaptic cleft.
D. Anesthetic disturbs the working of acetylcholinesterases to hinder the breakdown of neurotransmitters.
E. All of the above.
9. _____________ contains gray matter inside and white matter outside, whereas _____________ contains white matter inside and gray matter outside.
A. Cerebrum, spinal cord
B. Spinal cord, cerebrum
C. Spinal cord, cerebellum
D. Cerebellum, spinal cord
E. Spinal cord, medulla oblongata
10. Which of the following is NOT related to the peripheral nervous system?
A. Autonomic nervous system
B. Somatic nervous system
C. Sympathetic nervous system
D. Vagus nerve
E. None of the above
11. Which of the following statements about neurons are NOT true?
A. The parts of the neuron for accepting information are called dendrites.
B. Most damaged neurons cannot be repaired even though the cell body contains a nucleus.
C. Combining an axon with a Schwann cell produces a myelin sheath.
D. The important role of the synapse is to transmit message to other cells.
E. All are correct.
12. Which of the following is an INCORRECT statement about action potential caused by voltage-gated ion channels?
A. Depolarization begins with the opening of sodium channels and the closing of potassium channels.
B. In the resting state, there is no action potential as the neurons are in a negative state.
C. In the resting state, potassium ions are positioned inside the neurons and sodium ions are positioned outside the neurons.
D. The rising phase of action potential is the state of overcoming a threshold, opening sodium and potassium channels.
E. In the undershoot state, sodium channels are closed and potassium channels are opened.
13. Which of the following is part of the forebrain?
A. Cerebellum
B. Cerebrum
C. Pons
D. Medulla oblongata
E. Brainstem
14. Which of the following is NOT related to saltatory conduction?
A. Axons
B. Slow propagation of action potential
C. Nodes of Ranvier
D. Insulated myelin sheath
E. All are related to salutatory conduction.
15. A person who has lost motor coordination skills, balance, and sexual drive probably has damage to which parts of the brain?
A. Pons and medulla oblongata
B. Cerebellum and medulla oblongata
C. Cerebellum and hypothalamus
D. Cerebrum and pons
E. Hypothalamus and medulla oblongata
16. Action potential along an axon is usually conducted in _____________ direction(s) and transmission messages from presynaptic cells to postsynaptic cells are conducted in _____________ direction(s).
A. One, one
B. One, two
C. Two, two
D. Two, one
E. None of the above
Answers
1. A
Propagation of action potential is led by the influx of Na+ into neurons and efflux of K+ to the outside.
2. A
The order of the reaction of the nervous system:
Afferent (input sensory information) → Interneuron or Integration (processing information) → Efferent (output information to motor nervous) → Response
3. E
In the synaptic cleft the acetylcholine coming out of a presynaptic cell has three routes. One is bound to ligand-gated ion channels, another is reabsorbed by the presynaptic cell, and another is broken down by acetylcholinesterase on both presynaptic and postsynaptic membranes.
4. D
The sympathetic nervous system increases energy generation in response to stress. Therefore, the stimulation of the adrenal medulla, increase in the production of glucose, and acceleration of heart rate are vital responses to stress. However, an increase in digestion, such as stimulation of the gallbladder, is required in the parasympathetic division during rest.
5. D
Norepinephrine (NE) is the neurotransmitter released by postganglionic neurons and accepted on the adrenergic receptor. The neurotransmitter acetylcholine (AE) is released by preganglionic neurons in the sympathetic nervous system. It is also released by preganglionic and postganglionic neurons in the parasympathetic nervous system.
6. C
Bounded acetylcholine on the postsynaptic membrane opens cation channels. Depolarized membranes by influx of Na+ and efflux of K+ creates action potential and this spreads throughout the plasma membranes. Acetylcholine on the postsynaptic membrane does not directly affect the formation of synaptic vesicles.
7. D
Neurons are composed of dendrites, cell bodies, axons, and myelin sheath. Action potential is an electrical signal.
8. A
The main function of anesthetic is to block the opening of Na+ channels. The closed Na+ channels cannot produce action potential.
9. B
In the central nervous system the white matter is usually used for transporting information and the grey matter is for processing information. The white matter is situated inside the cerebrum and the grey matter is outside the cerebrum. In the spinal cord, the position of the white and gray matter are reversed.
10. E
All are related to the peripheral nervous system. The peripheral nervous system is divided into the autonomic nervous system (involuntary control) and the somatic nervous system (voluntary control). The autonomic nervous system is then divided into the parasympathetic and sympathetic nervous systems. The vagus nerve is contained in the parasympathetic nervous system to innervate the stomach, liver, large and small intestines, lungs, and heart.
12. D
All are true except D. During the rising phase the action potential overcomes the threshold, opening sodium channels and closing potassium channels, and creates a strong positive potential inside the membrane of the neurons.
13. B
Forebrain parts are cerebrum and diencephalon (thalamus and hypothalamus) and hindbrain parts are pons, medulla oblongata, and cerebellum.
14. B
Saltatory conduction means the fast conduction of action potential along the insulated myelin sheath.
15. C
The cerebellum controls motor coordination and balance, and the hypothalamus controls homeostasis and the basic feelings of desire, such as sexual drive, thirst, and hunger. The pons and medulla oblongata regulate the breathing rates. The cerebrum functions in integrating and analyzing sensory information for motor response.
16. A
Action potential along an axon is conducted in one direction because reopening of Na+ channels is prevented by a refractory period. The transmission message at the synaptic cleft is conducted in one direction as well, because the structures of presynaptic and postsynaptic cells are different from each other.