Nervous System
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| How do cells communicate? | Via electrical and chemical signals
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| What are 3 functions of the nervous system? | Sensory Input, Integration, Motor Output
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| What is sensory input? | Information gathered by sensory receptors about internal and external changes
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| What is integration? | Processing and interpretation of sensory output
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| What is motor output? | Activation of effector organs (muscles and glands) produces a response
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| What are effector organs? | Muscles and glands
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| What are the two divisions on the nervous system? | Central nervous system (CNS) & Peripheral nervous system (PNS)
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| What is part of the central nervous system? | Brain and spinal cord of dorsal body cavity
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| What does the central nervous system do? | Interprets sensory input and dictates motor output
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| What is part of the peripheral nervous system? | Mainly nerves that extend from the brain and spinal cord
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| What are spinal nerves? | Nerves that go to and from the spinal cord
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| What are cranial nerves? | Nerves that go to and from the brain
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| What are the two functional divisions of the peripheral nervous system? | Sensory (afferent) division and Motor (efferent) division
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| What fibers are part of the sensory (afferent) division? | Somatic sensory fibers and Visceral sensory fibers
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| What do somatic sensory fibers do? | Convey impulses from skin, skeletal, muscles, and joints to the central nervous system
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| What do visceral sensory fibers do? | Convey impulses from visceral organs to the central nervous system
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| What does the motor (efferent) division do? | Transmits impulses from the central nervous system to effector organs
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| What are the two divisions of the motor (efferent) division? | Somatic nervous system and Autonomic nervous system
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| What is the somatic nervous system composed of? | Somatic motor nerve fibers
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| What does the somatic nervous system do? | Conducts impulses from the central nervous system to skeletal muscle
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| Is the somatic nervous system a voluntary or involuntary nervous system? | Voluntary nervous system
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| What is the autonomic nervous system composed of? | Visceral motor nerve fibers
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| What does the autonomic nervous system do? | Regulates smooth muscle, cardiac muscle, and glands
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| Is the autonomic nervous system a voluntary or involuntary nervous system? | Involuntary nervous system
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| What are the two functional subdivisions of the autonomic nervous system? | Sympathetic and Parasympathetic
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| True or False: The parasympathetic and sympathetic subdivisions work in opposition to each other. | True
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| Is the sympathetic subdivision considered stressed or relaxed? | Stressed
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| Is the parasympathetic subdivision considered stressed or relaxed? | Relaxed
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| What are the two principal cell types? | Neuroglia and Neurons
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| What are neuroglia? | Small cells that surround and wrap delicate neurons
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| What are neurons (nerve cells)? | Excitable cells that transmit electrical signals
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| True or False: Nervous tissue is highly cellular and has little extracellular space, making it tightly packed. | True
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| Astrocytes: CNS or PNS? | CNS
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| Microglial cells: CNS or PNS? | CNS
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| Ependymal cells: CNS or PNS? | CNS
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| Oligodendrocytes: CNS or PNS? | CNS
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| Satellite cells: CNS or PNS? | PNS
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| Schwann cells: CNS or PNS? | PNS
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| What are astrocytes? | Most abundant, versatile, and highly branched glial cells
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| Where are astrocytes? | They cling to neurons, synaptic endings, and capillaries
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| Astrocytes ______ and ______ neurons. | support, brace
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| Astrocytes play a role in ______ between capillaries and neurons. | exchanges
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| Astrocytes guide the migration of ______ ______. | young neurons
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| Astrocytes control the chemical environment around _____. | neurons
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| Astrocytes respond to ______ ______ and ___________. | nerve impulses, neurotransmitters
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| Astrocytes influence ______ functioning and participate in ______ processing in the brain. | neuronal, information
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| What are microglial cells? | Small, ovoid cells with thorny processes
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| The thorny processes of the microglial cell _____ and _____ neurons. | touch, monitor
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| Microglial cells migrate toward ______ ______. | injured neurons
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| Microglial cells can transform to ________ microorganisms and neuronal debris. | phagocytize
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| Microglial cells are ______ cells in the central nervous system. | defensive
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| True or False: Ependymal cells range in shape. | True
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| True or False: Ependymal cells may be ciliated. | True
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| Ependymal cells line the central cavities of the ______ and ______ ______. | brain, spinal column
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| Ependymal cells form a ______ barrier between ______ ______ in cavities and ______ fluid bathing central nervous sytstem cells | permeable, cerebrospinal fluid, tissue
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| What are oligodendrocytes? | branched cells
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| Oligodendrocytes line up along the ______ nerve fibers in the central nervous system and wrap their processes around them. This produces an insulating covering called a ______ ______. | thicker, myelin sheath
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| What do satellite cells do? | Surround neuron cell bodies in the peripheral nervous system. (Similar to astrocytes of the central nervous system.)
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| What are Schwann cells (neurolemmocytes) similar to? | oligodendrocytes
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| Schwann cells surround all _______ nerve fibers and form _____ _____ around thicker nerve fibers. | peripheral, myelin sheaths
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| Schwann cells are vital to the ______ of ______ peripheral nerve fibers. | regeneration, damaged
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| What are neurons grouped by? | Direction in which the nerve impulse travels relative to the CNS.
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| What are the three types of neurons in functional classification? | sensory (afferent), motor (efferent), interneurons
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| Sensory neurons transmit impulses from _______ _______ toward the ______ nervous system. | sensory receptors, central
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| Almost all sensory neurons are ______. | unipolar
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| The cell bodies of sensory neurons lie in ______ in the ______ nervous system. | ganglia, peripheral
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| Interneurons lie between ______ and ______ neurons. | motor, sensory
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| Interneurons shuttle signals through ______ nervous system pathways. | central
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| True or False: Interneurons are 99% of the body's neurons. | True
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| Most interneurons are entirely within the _____ nervous system. | central
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| Motor neurons carry impulses from the _____ nervous system to _____. | central, effectors
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| Are motor neurons unipolar or multipolar? | multipolar
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| Most motor neuron cell bodies are in the ______ nervous system. | central
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| Neurons are the ______ units of the nervous system. | structural
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| What do neurons conduct? | impulses
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| How long do neurons last? | 100 years or more
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| True or False: Most neurons are amitotic. | True
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| Neurons have a _____ metabolic rate. | high
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| Neurons require a continuous supply of _____ and _____. | oxygen, glucose
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| All neurons have a _____ _____ and one or more ______. | cell body, processes
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| What are two words for the neuron cell body? | perikaryon or soma
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| What is the neuron cell body? | Biosynthetic center of neuron
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| What does the neuron cell body do? | Synthesizes proteins, membranes, and other chemicals
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| What are Nissl bodies? | Rough endoplasmic reticulum found in the neuron cell body and larger dendrites.
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| What's another name for Nissl bodies? | chromatophilic substance
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| What is the most active and best developed endoplasmic reticulum in the body? | Nissl bodies or chromatophilic substance
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| The neuron cell body has ______ nucleus with a _______. | spherical, nucleolus
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| Some cell bodies contain ______. | pigments
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| In most neuron cell bodies, the membrane of the neuron functions as a ______ surface. | receptive
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| Where are most neuron cell bodies located? | central nervous system
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| What are nuclei? | clusters of neuron cell bodies in the central nervous system
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| What are neuron processes? | arm like processes that extend from the body
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| The _______ nervous system contains both cell bodies and processes. | central
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| The _______ nervous system contains chiefly neuron processes. | peripheral
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| What are tracts? | bundles of neuron processes in central nervous system
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| What are nerves? | bundles of neuron processes peripheral nervous system
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| What are the two types of processes? | Dendrites and axons
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| Where are dendrites located? | In motor neurons
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| In motor neurons, _______ are hundreds of short, tapering , diffusely branched processes. | Dendrites
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| In motor neurons, _______ have the same organelles as the cell body. | dendrites
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| Dendrites are the _____ region of neuron. | receptive (input)
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| Dendrites convey incoming messages toward cell body as _____ ______. | graded potentials
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| What are graded potentials? | short distance signals
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| In many brain areas, fine dendrites are specialized to collect information with ______ ______. | dendritic spines
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| What are dendritic spines? | appendages with bulbous or spiky ends
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| _____ per cell arises from the _____ ______. | one, axon hillock
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| What is an axon hillock? | cone-shaped area of the cell body
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| In some neurons, the ______ is short or absent. In others, the _____ length takes up most of the cell. The ______ can be a meter long. (same answer for all) | axon
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| Long axons are called ______ ______. | nerve fibers
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| What are axon collaterals? | occasional branches
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| Distal endings are called ______ ______ or ______ ______. | axon terminals, terminal boutons
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| The axon generates _____ ______. | nerve impulses
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| The axon transmits nerve impulses along the ______ to the ______ ______. | axolemma, axon terminals
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| The axon terminals is the ______ region. | secretory
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| What do axon terminals do? | Release neurotransmitters to 'talk' to the next cell in the chain
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| Axon terminals can only release neurotransmitters to another _______, a _______, or _______ cell. | neurons, muscle, gland
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| _______ are released into the synapse. | neurotransmitters
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| What is the synapse? | extracellular space
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| Neurotransmitters either ______ or _______ neurons that the axon is in close contact with. | excite, inhibit
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| What does it mean when a neurotransmitter is excitatory? | The neurotransmitters will make a target neuron more likely to fire an action potential.
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| What does it mean when a neurotransmitter is inhibitory? | The neurotransmitters will make a target neuron less likely to fire an action potential.
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| _____ _____ carry on many conversations with different neurons at the same time. | axon terminals
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| The ______ lacks the rough endoplasmic reticulum and golgi apparatus. | axon
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| The axon relies on the cell body to renew ______ and ______. | proteins, membranes
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| The axon has efficient ______ mechanisms. | transport
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| The ______ quickly decays if cut or damaged. | axon
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| What is the myelin sheath? | segmented sheath around most long or large diameter axons
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| What is myelin? | whitish, protein-lipoid substance
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| What is the function of myelin? | it keeps ions in
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| The _______ _______ protects and electrically insulates the axon. | myelin sheath
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| The ______ _______ increases speed of nerve impulse transmission. | myelin sheath
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| Myelination in the peripheral nervous system is formed by ______ ______. | schwann cells
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| ______ ______ wrap around the axon in a jelly roll fashion. | schwann cells
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| One ______ ______ forms one segment of the myelin sheath. | schwann cell
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| ______ ______ is concentric layers of Schwann cell plasma that surrounds the axon. | myelin sheath
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| What is the outer collar of perinuclear cytoplasm (formally called neurilemma)? | peripheral bulge of schwann cell containing the nucleus and most of the cytoplasm
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| _______ _______ of myelinating cells have less protein. | plasma membranes
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| In the peripheral nervous system, the plasma membrane of myelinating cells has no _______ or _______. | channels, carriers
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| In the peripheral nervous system, the _______ ______ of myelinating cells has good electrical insulators. | plasma membrane
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| In which nervous system do plasma membranes of myelinating cells have less protein? | peripheral nervous system
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| What are myelin sheath gaps? | gaps between adjacent schwann cells
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| ______ ______ _______ are sites where axon collaterals can emerge. | myelin sheath gaps
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| What were myelin sheath gaps formerly called? | nodes of Ranvier
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| What are nonmyelinated fibers? | thin fibers not wrapped in myelin
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| ______ _______ are surrounded by schwann cells but no coiling. | nonmyelinated fibers
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| In the peripheral nervous system, one schwann cell may surround 15 different _____ _____. | nonmyelinated fibers
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| Myelin sheaths in the central nervous system are formed by multiple, flat processes of _______, not whole cells. | oligodendrocytes
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| Myelin sheaths in the ______ nervous system can wrap up to 60 axons at once. | central
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| The myelin sheath gap is present in both the central and peripheral nervous system. True or False | True
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| In the central nervous system, there is an outer collar of perinuclear cytoplasm. True or False | False
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| In the central nervous system, the thinnest fibers are _______. | unmyelinated
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| The _____ fibers are covered by long extensions of adjacent neuroglia. | thinnest
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| What is white matter? | regions of brain and spinal cord with dense collections of myelinated fibers
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| What is gray matter? | mostly neuron cell bodies and nonmyelinated fibers
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| ______ is required to separate charges across a membrane. | energy
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| ______ charges attract each other. | opposite
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| Energy is ______ when the charges move toward one another. | liberated
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| If opposite charges are separated, the system has ______ energy. | potential
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| Neurons are highly _______. | excitable
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| What is an adequate stimulus? | threshold
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| Neurons respond to adequate stimulus by generating an ______ ______. | action potential
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| What is an action potential? | nerve impulse
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| The _____ _____ of a single neuron is always the same strength regardless of stimulus. | action potential
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| Different neurons can have different _____ _____ strengths. | action potential
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| The speed of _____ _____ repetition can code for the intensity of experience. | action potential
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| Nerve signaling depends on _____ _____. | ion channels
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| _____ _____ serve as selective membrane ion channels. | large proteins
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| What are the two main types of ion channels? | leakage (nongated) and gated
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| ______ ion channels are always open. | leakage
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| In ______ ion channels, part of the protein changes shape to open or close the channel. | gated
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| What are three types of gated channels? | chemically gated (ligand-gated), voltage-gated, and mechanically (stretch) gated
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| _____ _____ channels open with the binding of a specific neurotransmitter. | chemically gated
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| _____ ______ channels open and close in response to changes in membrane potential. | voltage gated
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| _____ _____ channels open and close in response to physical deformation of receptors as in sensory receptors. | mechanically gated
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| When gated channels are open, ions diffuse quickly across membrane along ________ ________. | electrochemical gradients
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| What does it mean if an ion diffuses along an electrochemical gradient? | The ion is going from a higher concentration to a lower concentration and toward the opposite electrical charge.
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| What is the resting membrane potential? | the potential difference across the membrane of a resting cell
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| What is the resting membrane potential of neurons on the cytoplasmic side? | approximately -70mV
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| The membrane of neurons is termed as _______. | polarized
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| The ______ ______ _______ is generated by differences in the ionic makeup of intracellular fluid and extracellular fluid. | resting membrane potential
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| The ______ _______ ______ is generated by the differential permeability of the plasma membrane. | resting membrane potential
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| Extracellular fluid has a higher concentration of ______ than intracellular fluid. (type of ion) | Na+
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| The extracellular fluid is balanced chiefly by _____. (type of ion) | Cl-
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| Intracellular fluid has a higher concentration of _____ than extracellular fluid. (type of ion) | K+
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| The intracellular fluid is balanced by _______ _______ _______. | negatively charged proteins
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| The membrane is impermeable to ______ ______ ______. | large anionic proteins
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| The membrane is slightly permeable to ______ through leakage channels. (type of ion) | Na+
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| ______ diffuses into the cell down concentration gradient. | sodium
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| The membrane is 25 times more permeable to _____ than _____ because there are more leakage channels. (types of ions) | Na+, K+
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| ______ diffuses out of the cell down concentration gradient. | potassium
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| The membrane is quite permeable to _____. (type of ion) | Cl-
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| In the membrane, more ______ diffuses out than ______ diffuses in. | potassium, sodium
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| Is the cell more negative or more positive on the inside? | more negative
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| The differences in potassium and sodium diffusion establishes _____ _____ _____. | resting membrane potential
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| The ______-______ ______ stabilizes resting membrane potential. | sodium-potassium pump
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| The _____-______ _______ maintains concentration gradients for Na+ and K+. | sodium-potassium pump
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| The sodium potassium pumps ____ Na+ out of the cell and pumps ____ K+ into the cell. | three, two
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| Membrane potential changes are use as ______ ______. | communication signals
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| ______ ______ ______ when concentrations of ions across membrane change. | membrane potential changes
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| What are two types of signals that membrane potential changes? | graded potentials and action potentials
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| Membrane potential changes can produce ______ ______ which are incoming signals operating over short distances. | graded potentials
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| Membrane potential changes can produce ______ ______ which are long distance signals of axons. | action potentials
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| ______ ______ ______ are used as signals to receive, integral, and send information. | membrane potential changes
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| What is depolarization? | a decrease in membrane potential (toward zero and above)
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| When ______ occurs, the inside of the membrane becomes less negative than resting membrane potential. | depolarization
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| Does depolarization or hyperpolarization result in the increased probability of producing a nerve impulse? | depolarization
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| What is hyperpolarization? | an increase in membrane potential (away from zero)
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| When ______ occurs, the inside of the cell becomes more negative than resting membrane potential. | hyperpolarization
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| Does depolarization or hyperpolarization reduce the probability of producing a nerve impulse? | hyperpolarization
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| ______ potentials are mainly on dendrites. | graded
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| ______ potentials are short-lived, localized changes in membrane potential. | graded
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| When there is a stronger ______, there are more voltage changes and farther current flows. | stimulus
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| Can graded potentials only produce depolarization, only produce polarization, or can they produce both? | both depolarization and polarization
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| _____ potentials are triggered by stimulus that opens gated ion channels. | graded
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| ______ potentials dissipate quickly and decays. | graded
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| ______ potentials are signals only over short distances. | graded
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| ______ potentials are mainly on axons. | action
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| ______ potentials are the principle way that neurons send signals. | action
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| ______ potentials are the principal means of long-distance neural communication. | action
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| ______ potentials only occur in muscle cells and the axons of neurons. | action
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| ______ potentials create a brief reversal of membrane potential; with a change in voltage of ~100 mV. | action
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| _____ potentials do not decay over distance. | action
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| Each _____ channel has two voltage sensitive gates. (type of ion) | Na+
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| ______ gates are closed at rest. | activation
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| ______ gates open with depolarization allowing Na+ to enter the cell. | activation
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| ______ gates are open at rest. | inactivation
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| ______ gates block the channel once it is open to prevent more Na+ from entering cell. | inactivation
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| Each _____ channel has one voltage sensitive gate. (type of ion) | K+
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| _____ channels are closed at rest. (type of ion) | K+
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| _____ channels open slowly with depolarization. (type of ion) | K+
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| In the ______ state, all gated Na+ and K+ channels are closed. | resting
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| In the ______ state, only leakage changes for Na+ and K+ are open which maintains the resting membrane potential. | resting
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| In the ______ phase, ______ local currents open voltage gated Na+ channels which results in Na+ rushing into the cell. (same answer for both) | depolarizing
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| In the ______ phase, Na+ influx causes more _____ which opens more Na+ channels making intracellular fluid less negative. (same answer for both) | depolarizing
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| In the ______ phase, at the threshold positive feedback causes opening of all Na+ channels which causes a reversal of membrane polarity to +30mV and a spike of action potential. | depolarizing
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| In the ______ phase, the Na+ channel's inactivation gates slowly close. | repolarizing
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| In the ______ phase, membrane permeability to Na+ declines to resting state and the action potential spike stops rising. | repolarizing
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| In the _______ phase, voltage-gated K+ channels slowly open causing K+ to exit the cell and the internal negativity to be restored. | repolarizing
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| In the ______ phase, some K+ channels remain open, allowing excessive K+ efflux making the inside of the membrane more negative than the resting state. | hyperpolarization
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| In the _____ phase, there is a _____ of the membrane, meaning a slight dip below the resting voltage. (same answer for both) | hyperpolarization
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| In the _____ phase, Na+ channels begin to reset. | hyperpolarization
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| What is the order of the events that generate an action potential? | 1. resting state: no ions move through voltage-gated channels
2. depolarization: caused b Na+ flowing into the cell
3. repolarization: caused by K+ flowing out of the cell
4. hyperpolarization: caused by K+ continuing to leave the cell
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| Does repolarization reset electrical conditions or ionic conditions? | electrical conditions
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| After repolarization, _____-_____ pumps restore ionic conditions. | sodium-potassium
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| Do all depolarization events produce action potentials? | No
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| For an axon to "fire", depolarization must reach _____. | threshold
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| What is a threshold? | The voltage at which the action potential is triggered.
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| At ____, the membrane has been depolarized by 15 to 20 mV. | threshold
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| Na+ permeability increases at _____. | threshold
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| At _____, the Na+ influx exceeds K+ efflux. | threshold
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| The positive feedback cycle begins _____. | threshold
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| What is the all-or-none phenomenon? | an action potential happening completely or it not happening at all
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| _____ allows an action potential to serve as a signaling device. | propagation
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| In the propagation of an action potential, what causes local currents? (type of ion) | Na+
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| In the _______ of a(n) ______ ______, local currents cause depolarization of adjacent membrane areas in direction away from the action potential origin and toward the axon's terminals. | propagation, action potential
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| In the propagation of an action potential, do local currents trigger an action potential at the axon's terminals? | Yes
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| In the propagation of an action potential, does the action potential propagate towards the action potential origin? | No, it propagates AWAY.
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| True or False: Since Na+ channels closer to the action potential origin are inactivated, no new action potential is generated there. | True
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| True or False: Once initiated an action potential is self propagating. | True
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| Once the action potential is initiated, each successive segment of membrane depolarizes, then repolarizes in _______ axons. | nonmyelinated
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| True or False: Propagation in myelinated axons is the same in nonmyelinated axons. | False, they differ
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| True or False: All action potentials are completely different. | False, they are alike
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| True or False: All action potentials are independent of stimulus intensity. | True
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| How does the central nervous system tell the difference between a weak stimulus and a strong one? | The central nervous system determines stimulus intensity by the frequency of impulses.
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| True or False: Strong stimuli causes action potentials to occur more frequently. | True
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| Higher frequency means ____ stimulus. | stronger
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| True or False: When voltage-gated Na+ channels open the neuron cannot respond to another stimulus. | True
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| What is the absolute refractory period? | the time from the opening of Na+ channels until the resetting of the channels
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| The ______ ______ ______ ensures that each action potential is an all or none event. | absolute refractory period
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| The _____ ______ ______ enforces one way transmission of nerve impulses. | absolute refractory period
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| What follows the absolute refractory period? | relative refractory period
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| After the absolute refractory period, most ____ channels have returned to their resting state. | Na+
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| After the absolute refractory period, some ____ channels are still open. | K+
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| After the absolute refractory period, what is still occurring? | repolarization
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| During the relative refractory period, the _____ for action potential generation is elevated. | threshold
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| During the relative refractory period, the inside of the membrane is more ______ than the resting state. | negative
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| True or False: During the relative refractory period, a weak stimulus could stimulate an action potential. | False. Only an exceptionally strong stimulus could stimulate an action potential during the relative refractory period.
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| True or False: Conduction velocities of neurons vary widely. | True
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| What two things does the rate of action potential propagation depend on? | axon diameter and degree of myelination
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| True or False: Larger diameter fibers have less resistance to local current flow so there is faster impulse conduction. | True
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| What is the degree of myelination? | when continuous conduction in nonmyelinated axons is slower than the saltatory conduction in myelinated axons
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| _____ _____ insulate and prevent leakage of charge. | myelin sheaths
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| Saltatory conduction is only possible in ______ axons. | myelinated
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| Voltage-gated Na+ channels are located at _____ _____ _____. | myelin sheath gaps
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| Action potentials are generated only at myelin sheath _____. | gaps
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| Myelination causes ______ conduction which is about 30 times faster. | saltatory
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| The _____ ______ in saltatory conduction appears to jump rapidly from gap to gap. | electrical signal
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| What is multiple sclerosis? | an autoimmune disease affecting primarily young adults
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| What causes multiple sclerosis? | the immune system destroying myelin in the central nervous system and turning it into scleroses
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| What are sclerosis? | hardened lesions
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| _____ _____ causes impulse conduction slows and eventually ceases. | multiple sclerosis
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| _____ _____ causes demyelinated axons to increase Na+ channels. | multiple sclerosis
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| What does the increase Na+ channels caused by demyelinated axons cause? | cycles of relapse and remission
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| True or False: Visual disturbances are a symptom of multiple sclerosis. | True
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| True or False: Audio hallucinations are a symptom of multiple sclerosis. | False
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|
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| True or False: Weakness is a symptom of multiple sclerosis. | True
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|
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| True or False: Jaundice is a symptom of multiple sclerosis. | False
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|
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| True or False: Loss of muscular control is a symptom of multiple sclerosis. | True
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|
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| True or False: Gingivitis is a symptom of multiple sclerosis. | False
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| True or False: Speech disturbances are a symptom of multiple sclerosis. | True
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|
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| True or False: Loss of taste is a symptom of multiple sclerosis. | False
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|
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| True or False: Urinary incontinence is a symptom of multiple sclerosis. | True
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|
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| True or False: Hair loss is a symptom of multiple sclerosis. | False
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|
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| What is the treatment for multiple sclerosis? | drugs that modify immune system activity
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| What prevents multiple sclerosis? | high blood levels of vitamin D
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| The _____ system works because information flows from neuron to neuron. | nervous
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| Neurons are functionally connected by ______. | synapses
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| What are synapses? | junctions that mediate information transfer
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| What is the function of a presynaptic neuron? | it sends the information
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| The ______ ______ conducts impulses towards the synapse. | presynaptic neuron
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| What is the function of the postsynaptic neuron? | it receives the information
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| The _____ _____ transmits the electrical signal away from the synapse. | postsynaptic neuron
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| True or False: Most neurons can function as both presynaptic neurons and postsynaptic neurons. | True
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| _____ synapses are less common than _____ synapses. | Electrical, chemical
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| _____ synapses join neurons by gap junctions that connect cytoplasm of adjacent neurons. | Electrical
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| With _____ synapses, communication is very rapid. | electrical
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| _____ synapses may be unidirectional or bidirectional. | Electrical
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| _____ synapses synchronize activity. | Electrical
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| Electrical synapses are abundant in what kind of tissue? | embryonic nervous tissue
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| With electrical synapses, the nerve impulse remains ______. | electrical
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| Chemical synapses are specialized for release and reception of what kind of neurotransmitters? | chemical
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| How many parts are chemical synapses composed of? | two
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| The axon terminal of the presynaptic neuron and the neurotransmitter receptor region on postsynaptic neuron's membrane are parts of what kind of synapse? | chemical
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| In chemical synapses the axon terminal of the presynaptic neuron contains _____ _____ filled with neurotransmitter. | synaptic vesicles
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| The chemical synapse's neurotransmitter receptor region on the postsynaptic neuron's membrane is usually on the _____ or the _____ _____. | dendrite, cell body
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| The parts of the chemical synapse are separated the _____ _____. | synaptic cleft
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| With chemical synapses, a(n) ______ impulse changed to chemical across the synapse then back to ______. (same word) | electrical
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|
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| The _____ _____ is 30 - 50 nm wide and prevents nerve impulses from directly passing from one neuron to the next. | synaptic cleft
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| Transmission across the synaptic cleft is a ______ event. | chemical
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| The ____ ____ ensures unidirectional communication between neurons. | synaptic cleft
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|
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| Transmission across the _____ _____ depends on release, diffusion, and receptor binding of neurotransmitters. | synaptic cleft
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|
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| For information to transfer across chemical synapses, action potential arrives at the axon terminal of the ______ ______. This causes voltage - gated _____ channels to open. | presynaptic cleft, Ca2+
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|
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| In the information transfer across a chemical synapses, _______ protein binds to Ca2+ and promotes the fusion of synaptic vesicles with the axon membrane. | synaptotagmin
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|
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| _____ of neurotransmitter into the synaptic cleft occurs. | exocytosis
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|
||||
| In the information transfer across a chemical synapse, the ______ diffuses across . | neurotransmitter
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|
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| In the information transfer across a chemical synapse, the neurotransmitter binds to receptors on the ______ ______. | postsynaptic neuron
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|
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| In the information transfer across a chemical synapse, ion channels are ______. This causes a(n) ______ or ______ event (_____ potential). The neurotransmitter effects are terminated. | opened, excitatory, inhibitory, graded
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||||
| How many ways can neurotransmitter effects be terminated? | three
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|
||||
| _____ terminates neurotransmitter effects by astrocytes or axon terminal. | reuptake
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|
||||
| _____ terminates neurotransmitter effects by enzymes. | degradation
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|
||||
| _____ terminates neurotransmitter effects away from the synaptic cleft. | diffusion
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|
||||
| What is the synaptic delay? | the time needed for neurotransmitters to be released, diffuse across the synapse, and bind to receptors
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|
||||
| _____ _____ is the rate-limiting step of neural transmission. | synaptic delay
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|
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