A neurotransmitter can be either excitatory or inhibitory depending on the postsynaptic receptor.
The autonomic nervous system consists of the:
peripheral and afferent nervous systems
sympathetic and parasympathetic nervous systems
sympathetic and efferent nervous systems
parasympathetic and somatic nervous systems
Gray matter in the brain and spinal cord consists primarily of:
NERVE FIBERS
neuroglia
axons
cell bodies
Neurotransmitters are released in a synapse and bind to
presynaptic terminals
the synaptic cleft
the base of the axon
receptors on the postsynaptic neuron
Compared to the outside of the neuron, the inside has a negative positive equal none of the above( negative, positive, equal, none of the above ) charge.
When an impulse reaches a synapse
two nerve fibers come in direct contact
impulses will pass in either direction
an electrical spark will jump the gap
chemical transmitters are released
Along a neuron, the correct pathway for impulse conduction is
dendrite, axon, cell body, and receptor
dendrite, cell body, and axon
axon, cell body, and dendrite
receptor, axon, and cell body
Which is true of an action potential?
The plasma membrane is impermeable to Na+ and K+ ions.
Na+ ions move extracellularly.
The charges become equal on the outside and inside of the plasma membrane.
The outside of the plasma membrane is negatively charged and the inside is positively charged.
In the human nervous system:
most of the cells are neurons
most of the cells are glia cells
there are almost equal numbers of glia cells and neurons
the ratio of cells is unknown because of the complexity of the nervous system
Which of the following is a function of the central nervous system (CNS)?
integrating sensory information
evaluating the information
Initiating an outgoing response e are f
all of the above are functions
Small, distinct regions of gray matter within the CNS are called nuclei.
Interneurons reside:
in the CNS and peripheral nervous system
in the CNS only
in the peripheral nervous system only
none of the above
The central nervous system consists of the brain, spinal cord, and nerves.
Which of the following is true of spatial summation?
Simultaneous stimulation of more than one postsynaptic neuron occurs.
Impulses are fired in a rapid succession by the same neuron.
Neurotransmitters released simultaneously from several presynaptic knobs converge on one postsynaptic neuron.
Speed of impulse transmission is increased when several neurotransmitters are released.
A neuron that transmits a nerve impulse toward the central nervous system is called a(n):
motor neuron
sensory neuron
interneuron
bipolar neuron
Nerves that contain mostly afferent fibers are called:
sensory nerves
motor nerves
mixed nerves
Schwann nerves
The part of the nervous system that transmits impulses from the CNS to the skeletal muscle is the:
somatic nervous system
autonomic nervous system
central nervous system
afferent division
Which is true of a reflex arc?
It does not involve the brain.
It always consists of an afferent and an efferent neuron.
It always consists of an afferent neuron, an efferent neuron, and an interneuron.
It always consists of an afferent neuron, an efferent neuron, the brain, and the spinal cord.
The central nervous system is composed of efferent nerves only.
A synapse consists of:
a synaptic knob
a synaptic cleft
the plasma membrane of a postsynaptic neuron
all of the above