Chapter 27 Communication and Control 1: The Nervous System
Biology: A Guide to the Natural World, 5e (Krogh)
1) The cells of the nervous system that transmit nervous system messages are the:
A) glial cells.
B) dendrites.
C) synapses.
D) neurons.
Answer: D
Topic: Section 27.1
Skill: Knowledge/Comprehension
2) The parts of the central nervous system are the:
A) afferent and efferent.
B) nerves and receptors.
C) brain and spinal cord.
D) autonomic and somatic.
Answer: C
Topic: Section 27.1
Skill: Knowledge/Comprehension
3) The autonomic nervous system is a part of the:
A) central nervous system.
B) somatic nervous system.
C) peripheral nervous system.
D) appendicular nervous system.
Answer: C
Topic: Section 27.1
Skill: Knowledge/Comprehension
4) The portion of the nervous system that most directly controls skeletal muscles is the:
A) somatic.
B) autonomic.
C) sympathetic.
D) parasympathetic.
E) afferent.
Answer: A
Topic: Section 27.1
Skill: Knowledge/Comprehension
5) Cells in the central nervous system that are important for functions such as memory are the:
A) interneurons.
B) sensory neurons.
C) motor neurons.
D) glial cells.
Answer: A
Topic: Section 27.1
Skill: Knowledge/Comprehension
6) Which of the following would send a signal to the central nervous system that you had touched a hot object?
A) motor neuron
B) sensory neuron
C) interneuron
D) glial cell
Answer: B
Topic: Section 27.2
Skill: Knowledge/Comprehension
7) Which of the following does the central nervous system use for the action of pulling your hand away from a hot object?
A) receptors
B) sensory neurons
C) motor neurons
D) glial cells
Answer: C
Topic: Section 27.2
Skill: Knowledge/Comprehension
8) An organ or group of cells that responds to a motor neuron is a/an:
A) effector.
B) receptor.
C) glial cell.
D) sensory organ.
Answer: A
Topic: Section 27.2
Skill: Knowledge/Comprehension
9) White matter areas of the nervous system mostly contain:
A) neuron cell bodies.
B) myelinated axons.
C) cerebrospinal fluid.
D) ganglia.
Answer: B
Topic: Section 27.2
Skill: Knowledge/Comprehension
10) Nerves would be best described as:
A) collections of motor neuron dendrites and cell bodies.
B) collections of sensory neuron dendrites and cell bodies.
C) bundles of dendrites in the peripheral nervous system (PNS).
D) bundles of axons in the peripheral nervous system (PNS).
Answer: D
Topic: Section 27.2
Skill: Knowledge/Comprehension
11) When a neuron is at its "resting potential," which of the following is true about the concentration of sodium ions?
A) Sodium ions have a greater concentration inside the neuron's cell membrane.
B) Sodium ions have a greater concentration outside the neuron's cell membrane.
C) The sodium concentration is the same outside and inside the neuron's cell membrane.
Answer: B
Topic: Section 27.3
Skill: Knowledge/Comprehension
12) Part of the reason for the charge difference inside and outside a neuron's membrane is:
A) excess potassium outside the membrane.
B) excess sodium inside the membrane.
C) negatively charged proteins inside the membrane.
D) positively charged proteins inside the membrane.
E) positively charged proteins outside the membrane.
Answer: C
Topic: Section 27.3
Skill: Knowledge/Comprehension
13) A section of a neuron's membrane becomes temporarily positive on the inside when:
A) ion channels open and sodium ions rush in.
B) ion channels open and potassium ions rush in.
C) negatively charged proteins exit the cell.
D) neurotransmitters enter the cell.
Answer: A
Topic: Section 27.3
Skill: Knowledge/Comprehension
14) Inrushing sodium ions trigger the opening of nearby channels and movement of sodium inward at that neighboring section of the membrane. What is occurring?
A) normal resting potential
B) an action potential
C) neurotransmitter release
D) protein movement
Answer: B
Topic: Section 27.3
Skill: Knowledge/Comprehension
15) Which statement best describes how one neuron stimulates another?
A) Sodium ions jump across to the next neuron's membrane.
B) The neurons are physically connected, so the action potential continues movement.
C) Calcium ions diffuse across the synapse.
D) Neurotransmitter molecules diffuse across the synapse.
Answer: D
Topic: Section 27.3
Skill: Knowledge/Comprehension
16) A drug that causes potassium to leak out of the neuron would:
A) make it harder to trigger action potentials in the neuron.
B) cause the inside of the neuron to become more positive.
C) cause the outside of the neuron to become more negative.
D) make it easier to trigger action potentials in the neuron.
Answer: A
Topic: Section 27.3
Skill: Application/Analysis
17) Spinal nerves emerging from the spinal cord are named for:
A) their basic function.
B) the organ they supply.
C) the portion of the vertebral column around them.
D) strictly the number sequence 1—30.
Answer: C
Topic: Section 27.4
Skill: Knowledge/Comprehension
18) Axons of motor neurons first leave the spinal cord through the:
A) spinal nerve.
B) ventral roots.
C) dorsal roots.
D) dorsal root ganglion.
Answer: B
Topic: Section 27.4
Skill: Knowledge/Comprehension
19) In a reflex such as the "knee jerk" or patellar reflex, the efferent signal travels through the:
A) spinal cord.
B) motor neuron.
C) sensory neuron.
D) interneuron.
Answer: B
Topic: Section 27.4
Skill: Knowledge/Comprehension
20) Any collection of nerve cell bodies in the PNS is called a:
A) ganglion.
B) afferent nerve.
C) efferent nerve.
D) dendrite.
Answer: A
Topic: Section 27.4
Skill: Knowledge/Comprehension
21) Routine activities and energy conservation are controlled by the:
A) peripheral nervous system.
B) parasympathetic division.
C) sympathetic division.
D) thalamus.
Answer: B
Topic: Section 27.5
Skill: Knowledge/Comprehension
22) Which of the following would be a function of the sympathetic division?
A) stimulate the stomach
B) constrict the pupils
C) stimulate the gallbladder
D) accelerate heart rate
Answer: D
Topic: Section 27.5
Skill: Knowledge/Comprehension
23) You are giving first aid to a semiconscious person who (before your arrival) told a bystander something about taking a drug overdose. The person has dilated pupils and a dry mouth. You recall reading that many drugs "mimic" the effects of nervous system functions, and you quickly size up which part of the nervous system is being mimicked here. The bystander is calling 911. In order to save time and best advise the emergency dispatcher about the treatment EMTs should be prepared to begin when they arrive, you tell the bystander to tell the 911 operator that the drug taken probably mimics which nervous system division?
A) somatic
B) parasympathetic
C) sympathetic
D) sfferent
Answer: C
Topic: Section 27.5
Skill: Application/Analysis
24) Which of the following best describes the structural aspect of the cerebral cortex?
A) a thin band of gray matter making the outer layer of the cerebrum
B) a thick band of white matter making the outer layer of the cerebrum
C) a core of fast, myelinated axons in the interior of the brain
D) a cap of white matter over the spinal cord, made mostly of the thalamus
Answer: A
Topic: Section 27.6
Skill: Application/Analysis
25) Most sensory information is routed through which structure before arriving in the cerebrum?
A) pons
B) medulla oblongata
C) midbrain
D) hypothalamus
E) thalamus
Answer: E
Topic: Section 27.6
Skill: Knowledge/Comprehension
26) Which part of your brain processes the information in this question and, you hope, retrieves the information necessary to answer it?
A) cerebellum
B) cerebral cortex
C) pons
D) hypothalamus
E) midbrain
Answer: B
Topic: Section 27.6
Skill: Application/Analysis
27) The term "brain dead" may refer to the fact that all brain centers have ceased to function except the:
A) cerebrum.
B) cerebellum.
C) thalamus.
D) hypothalamus.
E) medulla oblongata.
Answer: E
Topic: Section 27.6
Skill: Knowledge/Comprehension
28) Proprioceptors provide us with:
A) sight.
B) hearing.
C) the sense of touch.
D) information about the position of the joints.
Answer: D
Topic: Section 27.7
Skill: Knowledge/Comprehension
29) Which of the following best describes sensory receptors?
A) Sensory receptors interpret sensation.
B) Sensory receptors translate action potentials into stimuli.
C) Sensory receptors translate stimulation into action potentials.
D) Sensory receptors work through efferent pathways.
Answer: C
Topic: Section 27.7
Skill: Application/Analysis
30) The Pacinian corpuscle is important to:
A) sight.
B) hearing.
C) the sense of touch.
D) information about the position of the joints.
Answer: C
Topic: Section 27.8
Skill: Knowledge/Comprehension
31) Our "oldest" sense, which works in a very similar way in insects, is the sense of:
A) vision.
B) hearing.
C) smell.
D) touch.
Answer: C
Topic: Section 27.9
Skill: Knowledge/Comprehension
32) Which statement about the sense of smell in humans is most accurate?
A) Smell is about equally as strong as taste.
B) One hundred different receptor varieties allow us to discern about 100 scents.
C) Combinations of over 300 receptors allow us to discern thousands of scents.
D) Ciliated cells rapidly move scent molecules to the brain for rapid analysis.
Answer: C
Topic: Section 27.9
Skill: Application/Analysis
33) The basic taste sensations are different in that each sensation works through:
A) a different chemical reaction route in a taste cell.
B) a similar chemical reaction route in a taste cell.
C) different ciliated receptor varieties, just like smell receptors.
D) different taste nerves.
Answer: A
Topic: Section 27.10
Skill: Application/Analysis
34) A person is blindfolded and then given a piece of apple to eat while the scent of pineapple is wafted around his or her nose. The person would most likely guess that he or she is eating a/an:
A) apple.
B) pineapple.
C) new type of fruit.
D) 50-50 mixture of apple and pineapple.
Answer: B
Topic: Section 27.10
Skill: Application/Analysis
35) The cochlea is part of the:
A) inner ear.
B) outer ear.
C) brain.
D) eye.
Answer: A
Topic: Section 27.11
Skill: Knowledge/Comprehension
36) The value of the three small bones of the middle ear is that they:
A) translate vibration into nerve impulses.
B) translate solid vibration into internal liquid vibration.
C) amplify vibrations by concentrating them into a smaller area.
D) connect the eardrum to the nerves of hearing.
Answer: C
Topic: Section 27.11
Skill: Application/Analysis
37) How do hair cells of the cochlea translate vibration into nervous impulses?
A) Bending cilia lead to ion flow and neurotransmitter release.
B) Pulling hairs trigger an action potential.
C) Vibrating hairs open voltage sensitive channels.
D) Moving cilia break molecules at their bases.
Answer: A
Topic: Section 27.11
Skill: Knowledge/Comprehension
38) The iris of the human eye is composed partly of:
A) nervous tissue.
B) empty space.
C) rods.
D) connective tissue.
E) smooth muscle.
Answer: E
Topic: Section 27.12
Skill: Knowledge/Comprehension
39) Which part of the human eye detects colored light?
A) enzymes in ganglion cells
B) rhodopsin molecules
C) aqueous humor
D) cones
E) cornea
Answer: D
Topic: Section 27.12
Skill: Knowledge/Comprehension
40) When light enters the eye, it is bent, or refracted, first by the:
A) retina.
B) cornea.
C) lens.
D) vitreous body.
Answer: B
Topic: Section 27.12
Skill: Knowledge/Comprehension
41) The brain and the spinal cord make up the central nervous system (CNS).
Answer: TRUE
Topic: Section 27.1
Skill: Knowledge/Comprehension
42) Any nerve that carries messages from the brain and spinal cord is an afferent division of the PNS.
Answer: FALSE
Topic: Section 27.1
Skill: Knowledge/Comprehension
43) Voluntary movement of the legs is controlled by the somatic nervous system.
Answer: TRUE
Topic: Section 27.1
Skill: Knowledge/Comprehension
44) Neurons are not true cells because they aren't spherical in shape.
Answer: FALSE
Topic: Section 27.2
Skill: Knowledge/Comprehension
45) A nerve is larger than a neuron.
Answer: TRUE
Topic: Section 27.2
Skill: Knowledge/Comprehension
46) The neuron being stimulated by a neurotransmitter comes after the synaptic cleft.
Answer: TRUE
Topic: Section 27.3
Skill: Knowledge/Comprehension
47) When a neuron is resting, it has a higher concentration of Na+ ions inside the cell membrane than outside.
Answer: FALSE
Topic: Section 27.3
Skill: Knowledge/Comprehension
48) The action potential moves across the synaptic cleft as an electrical signal.
Answer: FALSE
Topic: Section 27.3
Skill: Knowledge/Comprehension
49) The parasympathetic division of the autonomic nervous system would be key in preserving an individual who is escaping from a dangerous situation.
Answer: FALSE
Topic: Section 27.5
Skill: Application/Analysis
50) Damage to the medulla oblongata in the brain could interfere with breathing.
Answer: TRUE
Topic: Section 27.6
Skill: Application/Analysis
51) The human body has more sensory input to the CNS than the traditional "five senses."
Answer: TRUE
Topic: Section 27.7
Skill: Knowledge/Comprehension
52) If the left side of the body is paralyzed by a stroke or other brain injury, the damage occurred on the left side of the brain.
Answer: FALSE
Topic: Section 27.8
Skill: Application/Analysis
53) Different parts of the tongue are responsive to different tastes.
Answer: FALSE
Topic: Section 27.10
Skill: Knowledge/Comprehension
54) The cilia that respond to sounds in the cochlea have "trapdoor" channels for K+ ions.
Answer: TRUE
Topic: Section 27.11
Skill: Knowledge/Comprehension
55) Our visual system creates images as well as perceiving them.
Answer: TRUE
Topic: Section 27.12
Skill: Knowledge/Comprehension
Match the following.
A) bundle of axons
B) carries signals away from the CNS
C) glial membrane wrapping
D) carries signals to the CNS
E) mostly neuron cell bodies
56) Nerve
Topic: Section 27.2
Skill: Knowledge/Comprehension
57) Gray matter
Topic: Section 27.2
Skill: Knowledge/Comprehension
58) Afferent neuron
Topic: Section 27.2
Skill: Knowledge/Comprehension
59) Efferent neuron
Topic: Section 27.2
Skill: Knowledge/Comprehension
60) Myelin
Topic: Section 27.2
Skill: Knowledge/Comprehension
Answers: 56) A 57) E 58) D 59) B 60) C
Match the following. Answers may be used more than once.
A) somatic division
B) sympathetic division
C) parasympathetic division
61) Inhibits digestion
Topic: Section 27.5
Skill: Knowledge/Comprehension
62) Constricts pupils
Topic: Section 27.5
Skill: Knowledge/Comprehension
63) Stimulates skeletal muscles
Topic: Section 27.5
Skill: Knowledge/Comprehension
64) Stimulates salivation
Topic: Section 27.5
Skill: Knowledge/Comprehension
65) Accelerates heart
Topic: Section 27.5
Skill: Knowledge/Comprehension
Answers: 61) B 62) C 63) A 64) C 65) B
Match the following.
A) the "bridge" to the cerebrum
B) motor control and balance
C) regulates breathing and blood pressure
D) regulation of drives
E) reasoning and memory
66) Hypothalamus
Topic: Section 27.2
Skill: Knowledge/Comprehension
67) Pons
Topic: Section 27.2
Skill: Knowledge/Comprehension
68) Cerebellum
Topic: Section 27.2
Skill: Knowledge/Comprehension
69) Medulla oblongata
Topic: Section 27.2
Skill: Knowledge/Comprehension
70) Cerebrum
Topic: Section 27.2
Skill: Knowledge/Comprehension
Answers: 66) D 67) A 68) B 69) C 70) E
71) Motor neurons, which tell muscles to move, leave the spinal cord through the ________.
Answer: ventral root
Topic: Section 27.4
Skill: Knowledge/Comprehension
72) Which division of the autonomic nervous system stimulates digestion?
Answer: parasympathetic division
Topic: Section 27.5
Skill: Factual
73) A person is diagnosed with a brain tumor that is treated with radiation. The treatment is successful, but the doctor believes some brain damage occurred. The patient is constantly complaining of being thirsty, even though she has had plenty of water to drink. Which part of the brain is damaged in this patient and why?
Answer: The hypothalamus is a likely candidate because it controls drives such as the thirst drive.
Topic: Section 27.6
Skill: Application/Analysis
74) Which part of the brain is probably most involved with dreaming?
Answer: the cerebrum
Topic: Section 27.6
Skill: Application/Analysis
75) Why are sensory receptors often called transducers?
Answer: They must convert a signal in one form (such as light) into an electrical signal.
Topic: Section 27.7
Skill: Knowledge/Comprehension
76) In which part of the inner ear are vibrations converted into action potentials?
Answer: cochlea
Topic: Section 27.11
Skill: Knowledge/Comprehension
77) In which layer of cells in the eye is light converted into an electrical signal?
Answer: retina
Topic: Section 27.12
Skill: Knowledge/Comprehension
78) Novocain, or procaine, is a chemical that dentists use to numb your mouth before drilling. The chemical blocks the sodium gates on sensory neurons, preventing them from opening. Describe how this chemical decreases (One hopes!) the perception of pain.
Answer: Because the chemical prevents sodium gates on the sensory neuron from opening, no sodium enters the neurons. Sodium entering neurons is the signal for nearby channels to open, continuing the spread of sodium influx down the length of the axon. If sodium is blocked from entering voltage-regulated gates, the signal or action potential cannot move down the axon of the sensory neuron; thus, the brain won't be alerted to the sensation of pain.
Topic: Section 27.3
Skill: Application/Analysis
79) Imagine a person's spinal cord has been severed high enough that they feel nothing from their legs. Do the sensory neurons in their legs stop functioning? Explain your answer.
Answer: The sensory neurons are undamaged and continue functioning. The sensory neurons will still detect stimuli and send an impulse to neurons in the spinal cord. But the pathway running from spinal cord to brain has been cut above the level where the sensory neuron enters, so signals from these neurons won't be able to reach the brain; therefore, the brain won't sense anything.
Topic: Section 27.4
Skill: Synthesis/Evaluation
80) Humans have sophisticated, highly evolved brains that would be useful in directing all body activities. Yet we have the autonomic division and reflexes that intentionally bypass the conscious centers of the brain and directly handle some responses. Evaluate why this is useful. Also, propose situations to the contrary in which it might be useful to use the brain rather than an autonomic response, and explain why we respond as such anyway.
Answer: As remarkably fast as the brain works, it still takes time (even if a small amount of time) for a stimulus to pass from one neuron to the next. As small as the synaptic cleft is, it still relies on the relatively slow process of diffusion for the neurotransmitters of one neuron to pass a signal on to the next neuron. Reducing the number of neurons in a chain from stimulus to response may save that half-second or so that could mean the difference between falling and catching our balance. Additionally, there are some situations in which the response to a stimulus is unambiguous, and there is no reason to involve a decision-making process. Some of the simpler aspects of compensating for unbalanced movement to prevent falling or of being able to pull away from a burning object that is doing more damage every fraction of a second we are in contact with it are examples in which decision making in the brain would hardly ever be useful.
On the other hand, there are rare situations in which overruling a reflex would be useful, and we are largely powerless to do so. Many people would gladly endure an extra split second of pain in order to place, not drop, that expensive antique vase that has a sharp burr that has cut our hand. Something innocuous that has nonetheless startled us and sent our fight or flight response into overdrive would be preferable to ignore. Yet, in the evolutionary balance sheet, being over-prepared for such responses must have been of greater survival value than not having those reflexes and autonomic responses.
Topic: Section 27.5
Skill: Synthesis/Evaluation
Refer to the figure below, and then answer the question that follows.
81) The part of the brain indicated by a "1" corresponds to the:
A) thalamus.
B) hypothalamus.
C) medulla oblongata.
D) cerebellum.
Answer: D
Topic: Section 27.6
Skill: Knowledge/Comprehension
Refer to the figure below, and then answer the question that follows.
82) The missing label indicated by a "2" corresponds to the:
A) malleus.
B) oval window.
C) cochlea.
D) tympanic membrane.
Answer: C
Topic: Section 27.11
Skill: Knowledge/Comprehension