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Campbell Essential Biology, 6e (Simon/Dickey/Hogan/Reece)
Chapter 27 Nervous, Sensory, and Locomotor Systems
Chapter 27 Learning Outcomes
27 Biology and Society: The Seismic Sense of Elephants
27 The Process of Science: How Do New Senses Arise?
27 Evolution Connection: Seeing UV
27.1. Describe adaptations for detecting sensory input in different animals and how those
adaptations evolved.
27.1 An Overview of Animal Nervous Systems
27.2. Describe the structures and functions of neurons, nervous tissue, and organs, and how
they are organized into and work together in the central and peripheral nervous systems
and the different divisions of the peripheral nervous system.
27.3. Describe how electrical signals are sent through a neuron and into a receiving cell,
including the cellular structures and chemicals needed, and how drugs can alter
transmission of electrical signals.
27.2 The Human Nervous System: A Closer Look
27.4. Describe how neuroplasticity contributes to the normal functioning of the brain, and how
alterations in neurological function are associated with diseases of the nervous system.
27.3 The Senses
27.5. List and describe the components of signal transduction, and explain how signal
transduction is related to sensing and responding to external and internal conditions.
27.6. List and describe sensory systems that detect different environmental stimuli, including
how sensory structures are related to their functions, and how alteration of structures
leads to a loss of sensory function.
27.4 Locomotor Systems
27.7. Describe the structures, arrangement, and functions of the components of bones and
joints, and how skeletal injury and disorders occur and are treated.
27.8. Describe the structures, arrangement, and functions of the components of a muscle.
27.9. Explain how a motor neuron signals a muscle fiber to contract, and describe an example
of an animal using its sensory receptors, central nervous system, skeleton, and muscles to
perform an activity.
Global learning outcomes
1. Demonstrate an understanding of the principles of scientific inquiry.
2. Demonstrate the ability to think critically and employ critical-thinking skills.
3. Read and interpret models, graphs, and data.
4. Demonstrate the quantitative skills needed to succeed in biology.
5. Demonstrate an understanding of the impact of science on society.
6. Evaluate the credibility of scientific information from various sources.
7. Demonstrate the ability to make connections between concepts across biology.
8. Communicate effectively in writing.
9. Apply the scientific method to interpret information and draw conclusions.
27.1 Multiple Choice Questions
1) What evolutionary adaptation allows elephants to migrate, meet, and mate over great
distances?
A) echolocation
B) electroreception
C) magnetoreception
D) seismic detection
2) The two major divisions of the nervous system are the ________.
A) sympathetic and parasympathetic
B) central nervous system (CNS) and peripheral nervous system (PNS)
C) sensory and motor
D) voluntary and involuntary
3) The cells that carry electric signals from one part of the body to another in the nervous system
are ________.
A) dendrites
B) neurons
C) effectors
D) synapses
4) In the nervous system, integration ________.
A) occurs at the axon
B) inevitably results in the attainment of a threshold potential
C) is the analysis and interpretation of sensory signals and the formulation of appropriate
responses
D) is the assimilation of memories
5) Which of the following neurons are part of the peripheral nervous system?
A) sensory neuron and motor neuron
B) interneuron neuron and motor neuron
C) interneuron neuron and sensory neuron
D) only motor neurons
6) Multiple sclerosis involves primarily ________.
A) destruction of the medulla oblongata
B) deterioration of the corpus callosum
C) destruction of the myelin sheath
D) deterioration of parts of the spinal cord
7) Which of these carry incoming messages toward the cell body of a neuron?
A) axons
B) dendrites
C) actin filaments
D) supporting cells
8) Outnumbering neurons by up to 50 to 1, which cells protect, insulate, and reinforce neurons?
A) sensory cells
B) motor cells
C) satellite cells
D) supporting cells
9) The minimum change in a membrane’s voltage that must occur to trigger an action potential is
called the ________.
A) threshold
B) synaptic terminal
C) membrane potential
D) resting potential
10) What causes the inside of a membrane to become positively charged during an action
potential?
A) Negatively charged ions rush out.
B) Positively charged ions rush in.
C) Positively charged ions rush out.
D) Negatively charged ions rush in.
11) The movement of an action potential along a neuron is most like ________.
A) the ripples created by dropping a pebble into a pond, gradually decreasing in size as the
waves spread apart
B) a crowd at a sporting event doing the wave around a stadium
C) a radio tower emitting a signal that reaches only a small region
D) the sound of your voice spreading out as you yell loudly to your friend while at a park
12) A neuron can relay a more intense signal by ________.
A) sending a stronger action potential
B) sending more action potentials in a given amount of time
C) sending an action potential that travels more quickly
D) sending a longer action potential
13) In a chemical synapse, what is the name of the gap between the sending and receiving cells?
A) synaptic terminal
B) action potential
C) synaptic cleft
D) myelin sheath
14) Which of the following neurotransmitters is associated with sleep, mood, attention, and
learning?
A) acetylcholine
B) epinephrine
C) serotonin
D) endorphins
15) Which of the following statements is TRUE?
A) Heroin binds to endorphin receptors.
B) Caffeine increases the effects of neurotransmitters that normally suppress nerve signals.
C) Alcohol is a stimulant.
D) Nicotine is a depressant.
16) Where would we expect to find electrical synapses?
A) within the brain
B) within the heart
C) within the spinal cord
D) between interneurons and motor neurons
17) Which of the following is(are) part of the central nervous system?
A) motor system
B) brain and spinal cord
C) brain only
D) spinal cord only
18) What part of the nervous system cushions the CNS and helps supply it with nutrients and
hormones, and carries away wastes?
A) cerebrospinal fluid
B) spinal cord
C) interneurons
D) the bones of the skull
19) Which of the following effects could result from activation of the sympathetic nervous
system?
A) decreased heart rate
B) stimulated digestive organs
C) secretion of epinephrine
D) narrowing of the bronchi
20) Realizing that you did not study as much as you needed to for this exam, you start to take the
test. However, it is difficult to concentrate because your heart is racing, your stomach seems tied
in a knot, you are breathing too quickly, and your mouth is dry. Most likely, you are
experiencing the effects of the ________.
A) motor nervous system
B) sympathetic division
C) parasympathetic division
D) central nervous system
21) You start to trip, but you keep your balance and don’t fall. Which of the following brain
regions is responsible for the rapid coordination of muscle activity that kept you from falling?
A) cerebral cortex
B) thalamus
C) cerebellum
D) cerebrum
22) Which, if any, of the following types of personal characteristics are based in the cerebral
cortex?
A) reasoning abilities only
B) artistic talents only
C) personality traits only
D) reasoning abilities, artistic talents, and personality traits
23) Which one of the following correctly pairs the structure with its major function(s)?
A) hypothalamus–regulates body temperature, blood pressure, and hunger
B) cerebellum–regulates memory, learning, and speech
C) brainstem–is the input center for sensory data going to the cerebrum
D) thalamus–coordinates balance
24) The cerebral cortex is highly folded. Why might this be an advantage for the functions of the
cerebrum?
A) The increased surface area increases the area for higher-level thinking.
B) The increased surface area permits greater contact between the cerebrum and the cerebellum.
C) The folds form grooves that let the bones of the skull reach deeply down between brain
regions.
D) The folds increase the areas where sensory receptors can reach the brain’s surface.
25) Which of the following was supported by the terrible accident that happened to Phineas
Gage?
A) The cerebrum plays a major role in the sense of balance.
B) You cannot live without your hypothalamus.
C) The frontal lobes are associated with personality.
D) The pons plays a crucial role in hearing.
26) Alzheimer’s disease is characterized by ________.
A) mental deterioration, memory loss, and personality changes
B) extreme mood swings
C) loss of energy and suicidal thoughts
D) increased energy and extreme talkativeness
27) The receptor potential is the ________.
A) membrane potential produced when a neurotransmitter molecule binds to its receptor
B) membrane potential produced in the receptor cell by sensory transduction
C) membrane potential produced as an all-or-none phenomenon
D) membrane potential produced at a muscle cell
28) Which of the following is an example of sensory adaptation of receptors?
A) going into deep sleep
B) distinguishing between different colors
C) ignoring the shoes on your feet
D) detecting sound and light simultaneously
29) In contrast to action potentials, receptor potentials ________.
A) are all-or-none phenomena
B) vary in intensity
C) do not require a stimulus
D) do not rely on changes in the membrane potential
30) In all types of chemoreceptors, receptor cells develop receptor potentials in response to
________.
A) changes in the movement of the surrounding molecules
B) the electrical properties of the surrounding cells
C) chemicals dissolved in a fluid such as blood or saliva
D) the addition of positively charged proteins
31) Standing out in center field, the baseball player watches the hitter’s bat strike the ball and
then, slightly later, hears the sound of the impact. What types of sensory receptors did the player
just use?
A) thermoreceptors and chemoreceptors
B) photoreceptors and mechanoreceptors
C) chemoreceptors and pain receptors
D) pain receptors and thermoreceptors
32) Thermoreceptors detect ________.
A) motion
B) sound
C) pressure
D) temperature
33) Which one of the following statements is TRUE?
A) Cones are more sensitive to light than rods.
B) Rods can distinguish color.
C) There are three different types of cones in the human eye.
D) The human retina is completely covered with photoreceptors.
34) A person who cannot focus well on distant objects has ________.
A) farsightedness
B) nearsightedness
C) astigmatism
D) cataracts
35) A person who has blurred vision caused by a misshapen lens or cornea has ________.
A) farsightedness
B) nearsightedness
C) astigmatism
D) cataracts
36) A person whose eyeball is shorter than normal suffers from ________.
A) farsightedness
B) nearsightedness
C) astigmatism
D) cataracts
37) The organ of Corti is in the ________.
A) outer ear
B) inner ear
C) middle ear
D) eardrum
38) When you hear, the ________ vibrates.
I) eardrum
II) hammer
III) stirrup
A) I
B) II
C) III
D) I, II, and III
39) Some adults with attention deficit hyperactivity disorder (ADHD) have abnormally low
activity of the neurotransmitter involved in pleasure, attention, memory, sleep, movement, and
learning, which increases their risk of drug abuse. Which drug are they most likely to abuse?
A) cocaine
B) morphine
C) codeine
D) alcohol