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