Ch7 The Nervous System
Anecephaly
-cerebrum fails to develop -failure to hear, see or process sensory inputs
Spina Bifida
-incomplete vertebrae formation -paralyzed lower limbs -inability to control the bowels and bladder
Cerebral Palsy
-possible mental retardation and impaired hearing or vision - Neuromuscular disability, possibly from temporary oxygen loss. -Spastic, poorly controlled muscles
Which of the following statements regarding the nerve impulses is true?
A stimulus changes the permeability of a patch of the membrane and sodium ions (Na+) diffuse rapidly into the cell.
__________ neurons carry an impulse to the CNS.
Afferent
Which of these is a sympathetic effect?
Blood vessels constrict.
Central Nervous System
CNS; brain and spinal cord; integrating and command center
Which of the following brain dysfunctions is also known as a stroke?
CVA
In a ______, the victim may be dizzy, "see stars", or lose consciousness
Concussion
The cell bodies of sensory neurons whose fibers enter the spinal cord are found in the __________.
Dorsal root Ganglion
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
Why is white matter "white"?
It contains a high concentration of myelin.
________ cells form the myelin sheaths around nerve fibers in the PNS.
Schwann
Supporting cells in the PNS include __________ that form the myelin sheaths and satellite cells that act as protective cushioning cells.
Schwann Cells
Cervical Plexus
Serves the diaphragm, shoulders and neck Phrenic nerve
Anesthetics work by blocking the movement of an ion into an axon, thus preventing an action potential from being generated. Which ion is being blocked?
Sodium
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
What is the most abundant glial cell in the central nervous system (CNS)?
astrocytes
Which of the following conditions would result from damage to the cerebellum?
ataxia
The cerebellum aids in maintenance of __________.
balance and posture
The __________ nervous system includes the brain and spinal cord.
central
What produces cerebrospinal fluid (CSF)?
choroid plexus
Which of these is an effect of the parasympathetic nervous system?
increases peristalsis within the stomach and small intestines
Which of these is a deep pressure receptor?
lamellar corpuscle
Spinal nerves are _____ nerves.
mixed
All motor and association neurons are __________.
multipolar
Collectively, the supporting cells in the CNS are called __________.
neuroglia
What part of the brain do we use when initiating skeletal muscle movement?
primary motor area
Which of these lists the components of a reflex arc in the correct sequence?
receptor; afferent neuron; control center; efferent neuron; effector
__________ reflexes regulate skeletal muscle.
somatic
What cranial nerve pair supplies many organs in the ventral body cavity?
vagus nerves
________ reflexes include the secretion of saliva, changes in the size of our pupils, and digestion involve the activities of smooth muscles.
automatic
What part of a neuron receives signals and sends a message to the cell body?
dendrite
Typically, little permanent brain damage occurs in a ____.
Concussion
A brain ________ is the result of marked tissue destruction.
Contusion
In a severe case, a ________ results in a coma.
Contusion
Damage to which cranial nerve(s) may impair the sense of taste?
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 statement describes a function of the spinal cord?
The spinal cord sends sensory information to the brain and carries motor signals from the brain to motor neurons.
The brain dysfunction where blood supply to a region (or regions) of the brain is blocked and vital brain tissue dies, as by a blood clot or a ruptured blood vessel, is called ________.
cerebrovascular accidents (CVAs) {stroke}
Which one of the following is the correct sequence of nerves that exit the spinal cord, from superior to inferior?
cervical spinal nerves, thoracic spinal nerves, lumbar spinal nerves, sacral spinal nerves
Which spinal plexus gives rise to the phrenic nerve, and what organ does this nerve supply?
cervical; diaphragm
The __________ produce cerebrospinal fluid.
choroid plexuses
Usually, brain injury is slight in a ______.
concussion
The axon of a neuron __________.
conducts nerve impulses away from the neuron cell body
Together with the brain stem, the __________ oversees all subconscious, autonomic functions.
diencephalon
The deep groove that separates the two hemispheres of the cerebrum is called the __________.
longitudinal fissue
The fissure in the brain that separates the two cerebral hemispheres is called the ________.
longitudinal fissure
The three connective tissue membranes covering and protecting CNS structures are collectively known as the __________. The __________ is the outermost, leathery layer.
meniges; dura mater
The nervous system gathers and interprets information, and then effects a response through a process called __________.
motor output
Which of the following is NOT a central nervous system glial cell?
neuron
Between successive Schwann cells, there are gaps in the myelin sheath called __________.
nodes of Ranvier
Cranial nerve III is known as the ________ nerve.
oculomotor
The corpus callosum connects the __________.
right and left cerebral hemispheres
Brachial Plexus
serves thorax and upper appendages medial and ulnar nerves Axillary and radial nerves
Which division of the peripheral nervous system activates skeletal muscles?
somatic nervous system
The __________ division of the autonomic nervous system allows us to initiate the fight-or-flight response in extreme circumstances.
sympathetic
To measure the electrical activity of brain neurons, electrodes are placed at various points on the scalp and connected to a recording device. The patterns of electrical activity of the neurons are called brain waves. Brain waves are unique and can be used to diagnose disorders in the brain.
*Alpha brain waves are typical relaxed, awake states. *Beta brain waves of typical alert, awake status. *Theta brain waves are common in children. *Delta brain waves of deep sleep.
Which of the following effects is characteristic of the parasympathetic nervous system?
*sensory (afferent) division
Both CVA and Alzheimer's Disease
-Language impairment -Memory loss -Short attention span -Disorientation and Confusion -Personality change
CVA Cerebrovascular Accidents
-Paralysis -Brain damage due to a blocked blood supply -Numbness
Alzheimer's Disease
-Progressive brain degeneration
Events at a Synapses
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 receptors in the plasma membrane of the receiving neuron, causing ion channels there to open.
Physicians can use simple reflex tests to monitor the CNS. When reflex tests are abnormal, more sophisticated neurological tests may be ordered to try to localize and identify the problem. What is an electroencephalogram (EEG)? (select best answer) a) It is a nuclear medicine scan that gives a three-dimensional image. b) It is a tool that measures the patterns of electrical activity of the neurons in the brain. c) It is a scan using magnetic fields and radio waves to produce images of the body. d) It is a special X-ray to monitor blood flow in the brain.
It is a tool that measures the patterns of electrical activity of the neurons in the brain.
Peripheral Nervous System
PNS; Cranial and Spinal nerves; Communication lines with the body
Immediately after an action potential is propagated, which one of the following ions rapidly diffuses out of the cell into the tissue fluid ________.
Potassium
The __________ area that allows us to consciously move our skeletal muscles is anterior to the central sulcus in the __________ lobe.
Primary motor; frontal
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
Lumbar Plexus
Serves the lower abdomen, thighs and hips Femoral and Obturator nerves
Sacral Plexus
Serves the lower trunk, hip and lower appendages Sciatic and gluteal nerves
What is the first event of an action potential?
Sodium gates open and the membrane depolarizes.
Which of the following can adversely affect brain development?
alcohol
An action potential i) occurs when the graded potential is strong enough, ii) obeys the all-or-none rule, iii) is initiated by the opening of "gates" for sodium channels, iv) is characterized by a series of depolarizations/repolarizations along the membrane.
all statements are correct