A&P Chapter 7 Review
What statement regarding the nerve impulse is TRUE?
A stimulus changes the permeability of a "patch" of the membrane, and sodium ions (Na+) diffuse rapidly into the cell
What is NOT prevented from entering brain tissue due to the tight junctions that form the blood-brain barrier?
Essential amino acids
What is NOT a central nervous system glial cell?
Neuron
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 is 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
____ neurons carry an impulse to the CNS.
afferent
What can have an adverse affect on brain development in the fetus?
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 depolarization's/repolarizations along the membrane.
all statements are correct
What is the most abundant glial cell in the CNS?
astrocyte
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 is a sympathetic effect?
blood vessels constrict
The ____ nervous system, includes the brain and spinal cord.
central
Which spinal plexus gives rise to the phrenic nerve, and what organ does that nerve supply?
cervical; diaphragm
The ____ produce cerebrospinal fluid.
choroid plexus
What produces cerebrospinal fluid (CSF)
choroid plexus
The axon of a neuron ____.
conducts nerve impulses away from the neuron cell body
What part of a neuron receives signals and sends a message to the cell body?
dendrite
Together with the brain stem, the ____ oversees all subconscious, autonomic functions.
diencephalon
The cell bodies of sensory neurons whose fibers enter the spinal cord are found in the ____.
dorsal root ganglion
Which of these is an effect of the parasympathetic nervous system?
increases peristalsis within the stomach and small intestine
Why is white matter "white"?
it contains a high concentration of myelin
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)?
it is a tool that measures the patterns of electrical activity of the neurons in the brain
What is a deep pressure receptor?
lamellar corpuscle
The deep groove that separates the two hemispheres of the cerebrum 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.
meninges; dura mater
Like neurons, nerves are classified according to the direction in which they transmit impulses. Nerves carrying both sensory and motor fibers are called mixed nerves. Nerves that carry impulses toward the CNS only are called sensory, or afferent, nerves, whereas those that carry only motor fibers are motor, or efferent, nerves. Spinal nerves are ____ nerves.
mixed
The nervous system gathers and interprets information, and then effects a response through a process called __________.
motor output
All motor and association neurons are ____.
multipolar
Collectively, the supporting cells in the CNS are called ____.
neuroglia
Between successive Schwann cells, there are gaps in the myelin sheath called __________.
nodes of Ranvier
What part of the brain do we use when initiating skeletal muscle movement?
primary motor area
The __________ area that allows us to consciously move our skeletal muscles is anterior to the central sulcus in the __________ lobe.
primary motor; frontal
List the components of a reflex arc in order.
receptor, afferent neuron, control center, efferent neuron, effector
The corpus callosum connects the ___.
right and left cerbral hemispheres
What is the first event of an action potential?
sodium gates open and the membrane depolarizes
____ reflexes regulate skeletal muscles.
somatic
What 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
Damage to which cranial nerve(s) may impair the sense of taste?
the facial (N VII) and the glossopharyngeal (N IX)
What cranial nerve pair supplies many organs in the ventral body cavity?
vagus nerves