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Chapter Questions
Which type of animal has a nerve net?a. cnidariansb. planariansc. spongesd. All of these are correct
The most intelligent invertebrates are probably thea. annelids.b. arthropods.c. cephalopods.d. None of these can be regarded as intelligent.
The part of the brain that is seen only in mammals is thea. cerebellum.b. cerebrum.c. neocortex.d. olfactory bulb.
Which of these correctly describes the distribution of ions on either side of an axon when it is not conducting a nerve impulse?a. more sodium ions ($\mathrm{Na}^{+}$) outside and fewer potassium ions ($\mathrm{K}^{+}$) insideb. $\mathrm{K}^{+}$ outside and $\mathrm{Na}^{+}$ insidec. charged proteins outside; $\mathrm{Na}^{+}$ and $\mathrm{K}^{+}$ insided. charged proteins insidee. Both a and d are correct
When the action potential begins, sodium gates open, allowing $\mathrm{Na}^{+}$ to cross the membrane. Now the polarity changes toa. negative outside and positive inside.b. positive outside and negative inside.c. There is no difference in charge between outside and inside.d. None of these are correct.
Transmission of the nerve impulse across a synapse is accomplished bya. the release of $\mathrm{Na}^{+}$ at the presynaptic membrane.b. the release of neurotransmitters at the postsynaptic membrane.c. the reception of neurotransmitters at the postsynaptic membrane.d. Both a and c are correct.
Repolarization of an axon during an action potential is produced bya. inward diffusion of $\mathrm{Na}^{+}$.b. active extrusion of $\mathrm{K}^{+}$.c. outward diffusion of $\mathrm{K}^{+}$.d. inward active transport of $\mathrm{Na}^{+}$.
A drug that inactivates acetylcholinesterasea. stops the release of $\mathrm{ACh}$ from presynaptic endings.b. prevents the attachment of $\mathrm{ACh}$ to its receptor.c. increases the ability of $\mathrm{ACh}$ to stimulate postsynaptic cells.d. All of these are correct.
Which of these is not a specific function of the $\mathrm{CNS}$?a. generate motor outputb. perform integrationc. regulate blood sugard. receive sensory input
Which of the following is not part of the spinal cord?a. grey matterb. dorsal hornc. association areasd. tractse. ventral horn
The largest, outermost portion of the brain in humans is thea. cerebellum. $\quad$ c. reticular activating system.b. cerebrum. $\quad$ d. thalamus.
The limbic systema. includes the hippocampus and amygdala.b. is responsible for our deepest emotions, including pleasure, rage, and fear.c. is not responsible for reason and self-control.d. All of these are correct.
Which of these pairs is mismatched?a. cerebrum—thinking and memoryb. thalamus—motor and sensory centersc. hypothalamus—internal environment regulationd. cerebellum—motor coordinatione. medulla oblongata—fourth ventricle
A spinal nerve takes nerve impulsesa. to the $\mathrm{CNS}$.b. away from the $\mathrm{CNS}$.c. both to and away from the $\mathrm{CNS}$.d. only inside the $\mathrm{CNS}$.e. only from the cerebrum.
The autonomic system has two divisions, called thea. $\mathrm{CNS}$ and $\mathrm{PNS}$.b. somatic and skeletal systems.c. efferent and afferent systems.d. sympathetic and parasympathetic divisions.
Which of these statements about autonomic neurons is correct?a. They are motor neurons.b. Preganglionic neurons have cell bodies in the $\mathrm{CNS}$.c. Postganglionic neurons innervate smooth muscles, cardiac muscle, and glands.d. All of these are correct.
Sympathetic nerve stimulation does not causea. the liver to release glycogen.b. the dilation of bronchioles.c. the gastrointestinal tract to digest food.d. an increase in the heart rate.
Label this diagram of a reflex arc.