Chapter 12 Nervous Tissue

the sensory and motor divisions of the peripheral nervous system are further split into which two subdivisions? -autonomic and voluntary -proximal and distal -somatic and visceral -spinal cord and brain

somatic and visceral

neurons with a single process extending from the soma, such as the neurons that carry sensory signals to the spinal cord, are classified structurally as ____ neurons

unipolar

an axon lacking myelin sheath is said to be ___

unmyelinated

the all-or-none law of action potentials states which of the following? -a neurotransmitter should bind to all the receptors or to none of them -neurons have either a relative or an absolute refractory period -all neurons have the same resting membrane potential -a neuron will fire at maximum voltage if a stimulus depolarizes it to threshold

a neuron will fire at maximum voltage if a stimulus depolarizes it to threshold

since neurons generally do not undergo mitosis after reaching maturity, which organelle do they lack? -ribosomes -centrioles -golgi apparatus -endoplasmic reticulum

centrioles

the nervous system must interpret quantitative and qualitative information about its environment, thus is converts information to a meaningful pattern of action potentials. this process is called neural ___

coding

the respiratory center of the brain receives input from other parts (receptors for blood chemistry in arteries and stretch receptors in the lungs) to set a pattern of breathing. this is an example of which type of circuit? -diverging -reverberating -converging -parallel after discharge

converging

the ability of a neuron to enhance the effect of another neuron is called what? -spatial summation -temporal summation -facilitation -reverberation

facilitation

T/F: all neurotransmitters have an excitatory effect

false

the knotlike swelling in a nerve where neuron cell bodies are found is called an _____

ganglion

____ cells protect the neurons and help them function

glial

a shift in membrane voltage to a value that is more negative than the resting membrane potential is called ____

hyperpolarization

a negative membrane potential indicates which of the following? -both sides of the membrane are negatively charged -the outside of the membrane is negatively charged relative to the inside -both sides of the membrane are positively charged -the inside of the membrane is negatively charged relative to the outside

both sides of the membrane are negatively charged

the opposite of facilitation is presynaptic ____. this is a mechanism in which on presynaptic neuron suppresses another one

inhibition

which type of neuron lies within the CNS and carries out the integrative function of the nervous system? -autonomic -sensory -interneuron -motor

interneuron

which type of memory can store the most information? -short-term -immediate -working -long-term

long-term

which group of neurotransmitters are synthesized from amino acids by removal of the -COOH group? -purines -acetylocholine -monoamines -neuropeptides

monoamines

what creates electrical currents in neurons? -production of charged molecules called neurotransmitters -movement of actin and myosin filaments -movement of ions through channels -movement of free electrons

movement of ions through channels

this is the most common structural type of neuron. It contains one axon and multiple dendrites, and it is classified as an ___ neuron

multipolar

which two organ systems are primarily responsible for coordinating the other bodily systems to maintain homeostasis? select all that apply. -immune system -nervous system -cardiovascular system -endocrine system

nervous and endocrine system

which term describes the ability of neurons to process information, store and recall it, and make decisions? -retrograde transport -spatial summation -presynaptic inhibition -neural integration

neural integration

sensory, association and motor and the three classes of what? -neurotransmitters -neuroglia -ganglia -neurons

neurons

which term is used to refer to a cell membrane acorss which there is a separation of electrical charge, so that one side is more positive and the other side is more negative? -amphipathic -permeable -lipophillic -polarized

polarized

at a synapse, the neuron that responds to the neurotransmitter is the ___ neuron

postsynaptic

which ion has the greatest influence on the resting membrane potential of most neurons? -potassium -chloride -sodium -calcium

potassium

at a synapse, the neuron that releases neurotransmitter is the ___ neuron -presynaptic -postsynaptic

presynaptic

which term refers to the voltage difference (electrical potential) across the plasma membrane of a neuron when it is at rest and not engaged in electrical signaling? -local potential -postsynaptic potential -action potential -resting membrane potential

resting membrane potential

propagation of an action potential appears to "jump" from node to node is called ___ conduction

saltatory

which term is used to describe signal conduction along a myelinated axon? -migratory -local -saltatory -continuous

saltatory

the ____ (the cell body of a neuron) give rise to branch-like processes called ___ which are the primary site for receving signals from other neurons.

soma dendrites

which of the following are names for the cell body of a neuron? select all that apply -soma -astrocyte -ganglion -inclusion -neurosoma

soma and neurosoma

____ summation results when EPSPs occurring at multiple synapses add up to threshold at the axon hillock

spatial

there are two ways in which EPSPs can add up to produce enough activity to make a postsynaptic cell fire: temporal and spatial ____

summation

which term applies to the small swellings at the distal end of the axon of a neuron that contain synaptic vesicles? -synaptic knobs -axon hillocks -internodes -nodes of ranvier

synaptic knobs

which of the following best describes an electrical current? -the movement of charged particles like ions -a form of potential energy that can produce current -a positively or negatively charged atom or molecule -the opposition to the flow of electrical current across a membrane

the movement of charged particles like ions

which of the following best describes an electrical current? -the opposition to the flow of electrical current across a membrane -a form of potential energy that can produce current -the movement of charged particles like ions -a positively or negatively charged atom or molecule

the movement of charged particles like ions

which of the following are true about action potentials? -their amplitude is proportional to stimulus strength (graded) -they do not decrease with distance (nondecremental) -they only occur in dendrites -they may be excitatory or inhibitory

they do not decrease with distance (nondecremental)

what is the role of neural pools in the CNS? -to process information -to speed up nerve conduction -to produce neurotransmitter -to generate action potentials

to process information

Which of the following is most likely to be the resting membrane potential of a neuron? - +10 mV -+35 mV - 0 mV - -70 mV

-70 mV

the brain and spinal cord are components of the ___ nervous system, while the nerves and gangila are components of the ___ nervous system

-central -peripheral

which of the following are characteristics of local potentials? select all that apply. -all-or-none -decremental -self-propagating -graded

-decremental -graded

neurons that convey information to the CNS are called sensory neurons, or ____ neurons

afferent

a neuron with one axon and one dendrite is structurally classified as a ___ neuron

bipolar

which neurotransmitter is a catecholamine? -serotonin -glutamate -dopamine -acetylcholine

dopamine

motor, or ____ neurons carry signals away from the CNS and they lead to effectors (muscle and gland cells)

efferent

name the thin layer of fibrous tissue around myelin in nerve fibers of the peripheral nervous system -axolemma -endoneurium -varicosity -axoplasm

endoneurium