Exam #3 - Ch 7 The Nervous System
Peripheral Nervous System (PNS)
Consists of Cranial and spinal nerves; Communication lines with the body
Which of the following substances is/are NOT prevented from entering brain tissue due to the tight junctions that form the blood-brain barrier?
Essential amino acids
What is the first event of an action potential?
Sodium gates open and the membrane depolarizes.
autonomic
The ____________ nervous system is the part of the brain under involuntary, or automatic, control.
_______ neurons carry an impulse to the CNS. a. Multidirectional b. Afferent c. Efferent d. Static
afferent
__________ neurons carry an impulse to the CNS.
afferent
Neuroglia
are supporting cells of the nervous system.
What cells of the nervous system are responsible for anchoring neurons to their blood vessels and controlling the extracellular fluid concentrations of potassium and neurotransmitters?
astrocytes
The cerebellum aids in maintenance of __________.
balance and posture
What part of a neuron receives signals and sends a message to the cell body?
dendrite
The nervous system gathers and interprets information, and the correct response is sent out through a process called _______. a. integration b. motor output c. sensory input d. peripheral potential
motor output
The nervous system gathers and interprets information, and then effects a response through a process called __________.
motor output
All motor and association neurons are _______. a. multipolar b. Pacinian c. unipolar d. bipolar
multipolar
Collectively, the supporting cells in the CNS are called __________.
neuroglia
Between successive Schwann cells, there are gaps in the myelin sheath called _______. a. axons b. neuron cell bodies c. Nissl granules d. nodes of Ranvier e. axon hillocks
nodes of Ranvier
Between successive Schwann cells, there are gaps in the myelin sheath called __________.
nodes of Ranvier
Hemiplegia
one-sided paralysis
The __________ division of the autonomic nervous system allows us to initiate the fight-or-flight response in extreme circumstances.
sympathetic
During an action potential, the rapid decrease in sodium permeability and simultaneous increase in potassium permeability is responsible for __________.
the repolarization phase
What is the minimum number of neurons that can be involved in a reflex? a. One b. Two c. Four d. Three
two
Which of the following is a central nervous system glial cell? a. Astrocyte b. Ependymal cell c. Ependymal cell d. Microglia e. All of the above are CNS glial cells.
All of the above are CNS glia cells
How Synapses Work -- Events at a Synapse
1- An action potential arrives at the synaptic terminal 2- Calcium channels open, and calcium ions enter the synaptic terminal. 3- Vesicles containing neurotransmitter fuse with the plasma membrane of the sending neuron. 4- Neurotransmitter molecules diffuse across the synaptic cleft. 5- The neurotransmitter molecules bind to receptor in the plasma membrane of the receiving neuron, causing ion channels there to open.
Which of the following statements regarding the nerve impulse is TRUE? A. Ionic conditions are restored after repolarization by the actions of the sodium-potassium (Na+-K+) pump, whereby two Na+ ions are ejected for every three K+ ions carried back into the cell. B. At resting membrane potential, the extracellular compartment is slightly negative, and its intracellular space is slightly positive. C. If a stimulus is strong enough, hyperpolarization causes membrane polarity to be completely reversed, and an action potential is initiated. D. During repolarization, sodium ions diffuse rapidly into the cell. E. A stimulus changes the permeability of a "patch" of the membrane, and sodium ions (Na+) diffuse rapidly into the cell.
A stimulus changes the permeability of a "patch" of the membrane, and sodium ions (Na+) diffuse rapidly into the cell.
An action potential i) occurs when the local potential reaches threshold, ii) obeys the all-or-none rule, iii) proceeds with constant magnitude from one point to another, iv) is characterized by a series of depolarizations/repolarizations along the membrane. a. Only (i) and (iii) are correct. b. All the above statements are correct. c. Only (i), (ii), and (iii) are correct. e. Only (ii) and (iv) are correct. f. Only (iv) is correct.
All the above statements are correct.
Meningitis
An infection of the meninges is called
Which of the following is vital to the ability to speak? a. pyramidal tract b. Broca's area c. falx cerebri d. medulla oblongata
Broca's area
The _______ nervous system includes the brain and spinal cord. a. efferent b. central c. secondary d. peripheral
Central
Which of the following cranial nerves supplies motor fibers to the pharynx that promote swallowing and saliva production, and carries sensory impulses from taste buds of the posterior tongue and from pressure receptors of the carotid artery? A. Hypoglossal nerve (N XII) B. Glossopharyngeal nerve (IX) C. Facial nerve (N VII) D. Trigeminal nerve (N V) E. Vagus nerve (N X)
Glossopharyngeal nerve (IX)
The point at which there is no net movement of K+K+ into or out of the cell
Membrane potential of −−90 mVmV
The three connective tissue membranes covering and protecting CNS structures are collectively known as the __________. The __________ is the outermost, leathery layer.
Meninges; dura mater
The concentrations of which two ions are highest outside the cell?
Na+ and Cl−
Supporting cells in the PNS include _______ that form the myelin sheaths and satellite cells that act as protective cushioning cells. a. neurofibrils b. Schwann cells c. dendrites d. astrocytes
Schwann cells
Supporting cells in the PNS include __________ that form the myelin sheaths and satellite cells that act as protective cushioning cells.
Schwann cells
The cells that produce myelin in the peripheral nervous system (PNS) are called __________, and in the central nervous system (CNS) the cells are called __________.
Schwann cells; oligodendrocytes
What ion depolarizes the membrane when it diffuses into the axon of a neuron?
Sodium
Cerebrum
The conscious part of the brain is the
Damage to which cranial nerve(s) may impair the sense of taste?
The facial (N VII) and the glossopharyngeal (N IX)
Damage to which cranial nerve(s) may impair the sense of taste? a. Hypoglossal (N XII) b. Glossopharyngeal (N IX) c. Facial (N VII) d. The facial (N VII) and the glossopharyngeal (N IX)
The facial (N VII) and the glossopharyngeal (N IX)
Which of the following statements regarding the brain stem is FALSE?
The medulla oblongata plays a role in regulating the pituitary gland.
Which of the following statements regarding the brain stem is/are FALSE? a. The pons, a rounded structure that protrudes just below the midbrain, has important nuclei involved in the control of breathing. b. The corpora quadrigemina, located dorsally, are four rounded protrusions that are nuclei, which are reflex centers involved with vision and hearing. c. The neurons of the reticular formation are involved in motor control of the visceral organs. d. The medulla oblongata, in addition to containing many nuclei that regulate vital visceral activities, plays a role in consciousness and the awake/sleep cycles.
The medulla oblongata, in addition to containing many nuclei that regulate vital visceral activities, plays a role in consciousness and the awake/sleep cycles.
Depolarize
The membrane potential is becoming more positive than the resting membrane potential.
Hyperpolarize
The membrane potential is more negative than the resting membrane potential.
Repolarize
The membrane potential is moving from a more positive value toward resting membrane potential.
dorsal
The roots of the spinal cord on the posterior side are called _________ roots.
Besides the accessory nerve (XI), which pair of cranial nerves extends beyond the head and neck? a. Trigeminal (V) b. Hypoglossal (XII) c. Oculomotor (III) d. Facial (VII) e. Vagus (X)
Vagus (X)
The __________ nervous system includes the brain and spinal cord.
central
The _______ produce cerebrospinal fluid. A. adenohypophyseal glands B. meninges C. corpora quadrigemina D. crura cerebri E. choroid plexuses
choroid plexuses
The axon of a neuron __________.
conducts nerve impulses away from the neuron cell body
The dendrite of a neuron _______. A. is the only cell process of a multipolar neuron B. conducts nerve impulses away from the neuron cell body AND is the larger cell process of a multipolar neuron C. conducts nerve impulses toward the neuron cell body D. conducts nerve impulses away from the neuron cell body
conducts nerve impulses toward the neuron cell body
Central Nervous System (CNS)
consists of the brain and spinal cord; it Integrates and command center
Together with the brain stem, the _______ oversees all subconscious, autonomic functions. a. diencephalon b. central sulcus c. occipital lobe d. pyramidal tract
diencephalon
The cell bodies of sensory neurons whose fibers enter the cord are found in the _______. a. ventral root b. ventral root ganglion c. dorsal root ganglion d. autonomic ganglia e. basal nuclei
dorsal root ganglion
During the action potential, when does sodium permeability initially DECREASE?
during the peak of depolarization
autonomic reflexes
involuntary reflexes that regulates smooth muscle, heart, and gland activity
The deep groove that separates the two hemispheres of the cerebrum is called the _______. a. thalamus b. cerebellum c. central sulcus d. longitudinal fissure e. pons
longitudinal fissure
Dors-
means "back."
Cerebr-
means "brain."
-itis
means "inflammation" or "disease."
Neur-
means "nerve."
Auto-
means "self."
Let's consider a scenario in which the resting membrane potential changes from −−70 mVmV to +70 mVmV, but the concentrations of all ions in the intracellular and extracellular fluids are unchanged. Predict how this change in membrane potential affects the movement of Na+Na+. The electrical gradient for Na+Na+ would tend to move Na+Na+ __________ while the chemical gradient for Na+Na+ would tend to move Na+Na+ __________.
out; in
The __________ area that allows us to consciously move our skeletal muscles is anterior to the central sulcus in the __________ lobe.
primary motor; frontal
The corpus callosum connects the __________
right and left cerebral hemispheres
__________ reflexes regulate skeletal muscle.
somatic