Chapter 12 Drag and Drop
Place the following structures in the order that an electrical impulse would travel beginning with the postsynaptic membrane
1. Dendrites 2. Soma 3. Axon hillock 4. Internode 5. Node of ranvier 6. Terminal arborization 7. Synaptic knobs
Inhibitory
1. Dopamine 2. Acetylcholine 3. GABA 4. Glycine
Place each sentence into a logical order
1. The axon distal to the cut degenerates 2. The myelin portion of the Schwann cells around the damaged axon degenerates 3. Macrophages invade and phagocytize the degenerated myself 4. Schwann cells undergo mitosis and form a new column of cells 5. The regenerating axon forms serval atonal sprouts 6. One axon sprout forms a true axon, the other branches degenerate 7. Axon grow through the Schwann cell columns 8. New myelin sheaths are formed 9. Neurons reinnervate the structures they previously supplied
satellite cells
1. surrounding and insulating cells of the PNS that are found around the somas
An unmyelinated fiber has voltage-gated ion gates along its entire ______
Length
A damaged _______ nerve fiber may regenerate if its soma is intact and some neurilemma remains
Peripheral
Homeostasis
The ability to detect, interpret, and respond to changes in internal and external conditions. Nervous system is a necessary function
Place the events in the correct sequence. All items will NOT be used
1. Action potential reaches synaptic knob 2. Voltage-gated calcium channels open 3. Calcium enters the synaptic knob 4. Synaptic vesicles merge with synaptic knob plasma membrane 5. Neurotransmitter is released by exocytosis 6. Neurotransmitter crosses synaptic cleft 7. Neurotransmittter attaches to receptors on a muscle, neuron, or gland cell
Fill in the blanks with the appropriate terms and then place the events in the correct sequence
1. An inhibitory neurotransmitter binds to chemically-gated K+ channels 2. K+ channels open 3. K+ flows out of the neuron 4. The inside of the neuron becomes more negative 5. The IPSP propagates toward the axon hillock
Place the components of a peripheral nerve in sequence from outside to inside
1. Epineurium 2. Nerve 3. Perineurium 4. Fascicles 5. Endoneurium 6. Neurolemmocytes 7. Axolemma
multipolar neuron
1. Most common type of neuron 2. Have many dendrites and a single axon
Structural classification
1. Multipolar neuron 2. Bipolar neuron 3. Unipolar neuron
Anaxonic neuron
1. No axons are present 2. Only produce local potentials
Relative refractory period
1. Occurs when voltage-gated sodium channels have returned to resting state
Bipolar neuron
1. Relatively uncommon in humans 2. Have one axon and one dendrite
Reverberating circuit
1. Utilizes feedback to produce a repeated cyclical stimulation of the circuit 2. May continue to function until the cycle is broken by inhibitory stimuli or synaptic fatigue
Sapatial summation
1. Various locations of receptive segment are exposed to neurotransmitter 2. Multiple presynaptic neurons releasing neurotransmitter 3. Can generate an EPSP, IPSP, or both
schwann cells
1. form the myelin sheath in the PNS 2. function to insulate neurons and enhance the rate of transmission in the PNS
When a nerve fiber is cut the fiber distal to the injury ______ survive
Cannot
Resting membrane potential is created as a result of a greater net flow of positive charges from the ____________________
ICF to the ECF
The peripheral nervous system is further subdivided into an afferent (sensory) division and an efferent (_______________) division
Motor
Diverging circuit
Spreads information from one presynaptic neuron to several postsynaptic neurons
Action potentials arriving at the presynaptic terminal cause _________-gated calcium channels to open
Voltage
Fast atonal transport occurs at approximately ____________ millimeters per day. The mechanism involves movement along ___________. The power for this movement comes from specialized _____________ that split ATP to supply the energy needed. Substances can be moved in _____________. Slow atonal transport occurs at approximately __________ millimeters per day. This type of movement results from the ____________, and is also called _____________. The substances are move din ____________ direction only
1. 400 2. Microtubules 3. Motor proteins 4. Either direction 5. 0.1 to 3 6. Flow of the axoplasm 7. Axoplasmic flow 8. An anterograde
A synapse is the specific location where _________ is functionallly connected to either another neuron or _________. There are two types of synapses in the human body: chemical synapses and electrical synapses. Most synapses within the nervous system are __________ synapses
1. A neuron 2. An effector 3. Chemical
Unipolar neuron
1. A short process emerges from the cell body and branches like a T 2. Also called pseudounipolar 3. Have central and peripheral processes
Temporal summation
1. A single presynaptic neuron releases neurotransmitter 2. The same location of neuron is exposed to neurotransmitter in a very short period of time
Neurons are classified. Functionally according to the direction the _________ travels relative to the ____. Afferent neurons are the neurons of the sensory nervous system. They are responsible for conducting _______ input from both somatic sensory and visceral sensory receptors. Most sensory neurons are _________. Efferent neurons are the neurons of the motor nervous system, conducting _________ output from the CNS to the effectors. All motor neurons are _________. Interneurons (or __________ neurons) lie entirely within the CNS. They receive stimulation from many other neurons and carry out the integrative function of the nervous system. The most numerous types of neurons are _________
1. Action potential 2. CNS 3. Sensory 4. Unipolar 5. Motor 6. Multipolar 7. Association 8. Interneurons
Pumps move substances ____________ a concentration gradient, a process that requires ___________. Channels instead provide the means to move a substance _____________ a concentration gradient. Neurons contain the following major types of channels: Channels that are always open, allowing continuous diffusion of a specific ion from a region of ________ concentration to a region of _________ concentration are _________ channels. Channels that are normally closed that open in response to the binding of a __________ are ___________ channels. When open, they allow a specific ion to __________ across the plasma membrane Channels that are normally closed, but open in response to changes in _________ across the plasma membrane are ____________ channels. When open, they allow a specific ion to diffuse across the membrane
1. Against 2. Energy 3. With 4. High 5. Low 6. Leak 7. Neurotransmittter 8. Chemically-gated 9. Diffuse 10. Electrical charge 11. Voltage-gated
Nerve fibers are classified into three major groups called A, B, and C, based on their _____________. Group A has a conduction velocity that may be _______ per second; these fibers have both a ________ and are ________. Group B conducts at approximately ______ per second. Group C conducts at ________ per second. Group B and group C fibers generally have a _______ are are ___________.
1. Conduction velocity 2. 150 meters 3. Large diameter 4. Myelinated 5. 15 meters 6. 1 meter 7. Small diamter 8. Unmyelinated
Group A fibers
1. Conduction velocity = 150 m/sec 2. Large diameter 3. Somatic neurons from CNS to skeletal muscle 4. Myelinated
It is necessary that the neurotransmitter molecule is eliminated after each stimulation event. Its removal can occur by (1) ______________ which the neurotransmitter is chemically ___________ in the _____________ and (2) _____________, in which the neurotransmitter is re absorbed by a neurotransmitter _______________ in the membrane of the _______________ neuron. These neurotransmitters are "recycled" once packaged into another ____________ for reuse
1. Degradation 2. Inactivated 3. Synaptic cleft 4. Reuptake 5. Transport protein 6. Presynaptic 7. Synaptic vesicle
Excitatory
1. Dopamine 2. Norepinephrine 3. Acetylcholine 4. Glutamate 5. Substance P 6. Nitric oxide
There are approximately 100 known neurotransmitters, which can be classified into major groups: - Acetylcholine is a(n) ____________ neurotransmitter; it is released in both central nervous system and the peripheral nervous system - amino acids are the building blocks of _____________ and some also serve as neurotransmitters. Examples include glutamate, _______________ and aspartame -monoamines are derived from certain _____________ by the removal of a(n) __________ group and the addition of another function group. The functional group added determines whether the molecules belongs to the more specific subgroup called ______________ (norepinephrine, epinephrine, and ________________). -chains of amino acids that range in length from 2 to 40 amino acids are ________________. Examples of these include enkephalins and _________________.
1. Excitatory 2. Proteins 3. Glycine 4. Amino acids 5. Carbonyl 6. Cathecholamines 7. Dopamine 8. Neuropeptides 9. Somatostatin
Fill in the blanks with the appropriate terms and then place the events in the correct sequence. Some items will not be used
1. Excitatory neurotransmitter released from presynaptic neuron 2. Neurotransmitter binds to chemically-gated sodium channels 3. Sodium channels open 4. Sodium flows into neuron 5. Inside of neuron becomes more positive 6. This EPSP propagates toward the axon hillock
Local potentials
1. Ligand-gated sodium channels 2. EPSPs 3. IPSPs 4. Cause summation 5. Decremental 6. Reversible
The relative difference in charge across a plasma membrane is the ___________. This is more specifically called ________ in an inactive excitable cell. A __________ is used to measure the voltage difference across the plasma membrane. This is done by placing one microelectrode into the __________ and the other microelectrode outside the neuron into the _________. The RMP has a value, which is typically _____________ millivolts. The value is ___________ because the voltage of the cytosine is relatively negative compared to the voltage measured in the IF. More positive ions reside ________ a neuron than _______ a neuron when it is at rest
1. Membrane potential 2. Resting membrane potential 3. Voltmeter 4. Neuron 5. Interstitial fluid 6. -70 7. Negative 8. Outside 9. Inside
Sensory input
1. Nervous system receives numerous external and internal stimuli from receptors 2. Chemical receptors receive information for our sense of smell and taste 3. Some receptors receive information for external senses of touch or internal senses for blood pressure
Neuromodulation is the release of chemicals (other than ____________) from cells that locally regulate or alter the response of neurons to neurotransmitters. The substances released are called ___________. Neuromodulation generally results in either facilitation or inhibition. When there is greater response forum a postsynaptic neuron because of the release of neuromodulators it is __________. This may result from either ___________ amount of neurotransmitter in the synaptic cleft or ___________ number of receptors on postsynaptic neurons. When there is less response from a postsynaptic neuron because of the release of neuromodulators it is ____________. This results from either _____________ amount of neurotransmitters in the synaptic cleft or _________ number of receptors is postsynaptic neurons
1. Neurotransmitters 2. Neuromodulators 3. Facilitation 4. An increased 5. An increased 6. Inhibition 7. A decreased 8. A decreased
Items most prevalent in cytosol
1. Phosphate 2. Negatively charged proteins 3. Potassium
The __________ segment includes both dendrites and the cell body, which are the regions of the neuron that receive stimuli to excite the neuron. Channels in this region are _____________; no significant numbers of __________ channels are present The __________ segment is composed of the axon hillock. This segment contains voltage-gated channels. The ____________ segment is equivalent to the length of the axon. It contains voltage-gated channels The __________ segment includes the synaptic knob and contains voltage-gated channels and ______________
1. Receptive 2. Chemically-gated 3. Voltage-gated 4. Initial 5. Conductive 6. Transmissible 7. Pumps
Functional classification
1. Sensory neuron 2. Motor neuron 3. Interneurons neuron 4. Afferent neuron 5. Efferent neuron 6. Association neuron
Items more prevalent in IF
1. Sodium 2. Chloride
Integration
1. The brain can calculate if a response is needed to a stimulus 2. The spinal cord receives many senses and can send the information up the brain or out to a skeletal muscle
Control of muscles and glands
1. The motor neuron that stimulate skeletal muscles at the neuromuscular junction can arise from the spinal cord 2. The ability to run and swim is initiated by the brain and spinal cord 3. The nervous system controls salivation in response to food 4. Biofeedback can slow heart rates
Action potentials
1. Voltage-gated sodium channels 2. Voltage-gated potassium channels 3. Important for transmission over long distances 4. Require threshold
microglia
1. cells of the lymphatic system 2. macrophages of the CNS
ependymal cells
1. ciliated cells resembling epithelium 2. function in the production and circulation of CSF
a nervous system serves as the body's primary ______________ and control system. it provides a rapid means of _____________ and regulating body functions through electrical activity transmitted along specialized nervous system cells called _______________ to accomplish the following: Collect information. specialized nervous system structures called __________ monitor changes in both the internal and external environment called ____________. Process and evaluate information. after processing ____________ input, the brain and spinal cord determines what response, if any, is required. Initiate response to information. the brain and spinal cord initiate a response as _____________ output via nerves to _____________. these structures include all three types of muscle tissue and glands.
1. communication 2. integrating 3. neurons 4. receptors 5. stimuli 6. sensory 7. motor 8. effectors
astrocytes
1. most abundant CNS glial cells 2. involved with neurogenesis, scar formation, BBB maintenance, etc.
the __________ classification of nerves is based upon the _____________ from which the nerve extends: cranial nerves extend from the __________ and spinal nerves extend from the ___________. the ____________ classification of nerves is based upon whether a nerve contains sensory neurons or motor neurons. sensory nerves contain only sensory neurons that relay information ______________, and motor nerves contain primarily motor neurons that relay information ____________. in contrast, _________ nerves contain both sensory and motor neurons
1. structural 2. CNS component 3. brain 4. spinal cord 5. functional 6. to the CNS 7. from the CNS 8. mixed
the transmissive segment is the _______________. the main activity that occurs at the transmissive segment is the release of neurotransmitter from ____________. prior to the arrival of the action potential, ___________ embedded in the plasma membrane of a synaptic knob establish a _________________ concentration gradient by pumping it out to the IF. consequently, there is more calcium __________ of the synaptic knob than ___________ it.
1. synaptic knob 2. synaptic vesicle 3. calcium pumps 4. calcium 5. outside 6. inside
Place each of the following labels in the proper position on the curve when each of the indicated items would occur
A: 1. When sodium ions arrrive at the axon hillock, they depolarize the membrane at that point 2. Potential across the membrane is becoming less negative B: 1. At threshold, voltage-gated Na+ channels open quickly 2. Threshold 3. -55 mV 4. Sodium inflow is greater than at resting membrane potential or any other time C: 1. Voltage-gated potassium channels open D: 1. Hyperpolarization E: 1. Resting membrane potential 2. -70 mV
In order to maintain the electrochemical gradients for sodium and potassium, ATPase pumps move these ions ________ their respective gradients
Against
The motor division is separated further into a somatic motor division and a(n) _____________ motor division
Autonomic
Group C fibers
Conduction velocity = 1 m/sec
Group B fibers
Conduction velocity = 15 m/sec
This results in membrane _____________
Depolarization
Activated (open) sodium channels allow a rapid _______________ ions down their electrochemical gradient toward the ICF
Diffusion of sodium
The presynaptic membrane releases (via exocytosis) acetylcholine (ACh) into the ________
ECF of the synaptic cleft
The diffusion also movement of sodium and potassium across the membrane is driven at all times by the _____________
Electrochemical gradient
The afferent or sensory division transmits impulses. ______________________.
From peripheral organs to the CNS
The efferent or motor division transmits impulses ________________________.
From the CNS out to the peripheral organs
The movement of positive charges to the _______ causes the relative charge across the membrane to become positive on the inner surface
ICF
Converging circuit
Involves input that comes together at a single postsynaptic neuron
The diffusion of ____ into the cell or out of the cell causes a change in membrane potential
Ions
When K+ diffuses out of the cell, the cell becomes ____ depolarized
Less
Neurotransmitters combine with their receptor sites and cause ____________-gated ion channels to open
Ligand
The ACh binds to the ______________ channels after it diffuses across the synaptic cleft
Ligand-regulated sodium
When Na+ diffuses into the cell, the cell becomes _____ depolarized
More
K+ diffusing out of the cell has a ________ feedback effect on the initial polarization
Negative
Calcium ions diffuse into the cell and cause synaptic vesicles to release ______________
Neurotransmitters
Na+ diffusing into the cell causes more Na+ gates to open, which is a ________ feedback loop
Positive
Prior to the arrival of an action potential, the postsynaptic membrane is polar with a greater relative __________ charge compared to the ECF
Positive
Though potassium and sodium both leak through the membrane at rest, there is a greater diffusion Ak flow of ___________ at rest
Potassium
In somatic neurons, an action potential arrives at the synapse causing synaptic vesicles to fuse with the __________ membrane
Presynaptic
Neurotransmitters diffuse from the ___________ terminal across the synaptic cleft
Presynaptic
Near the sit of injury the basal lamina and the neurilemma form a ____________ tube
Regeneration
The depolarization causes a __________ that excites the entire membrane
Repetition
This continues until the traveling ______ reaches the end of the axon
Signal
Autonomic refers to the controls we are not aware of, like __________ muscle, cardiac muscles, and glands
Smooth
The electrical and chemical gradients for _________ are both high during resting membrane potential which results in a very high electrochemical gradient toward the inside of the cell
Sodium
When contact is established the ____ shrinks and reinnervated muscle fibers regrow
Soma
The tube guides the growing sprout back to the original target cells reestablishing ________ contact
Synaptic
Parallel-after-discharge circuit
Transmitted simultaneously along several neuron pathways to a common postsynaptic cell
An action potential at the _______ zone causes sodium to diffuse into the cell
Trigger
the voltage-gated Na+ channels _______ when the cell reaches +30mV
close
oligodendrocytes
for the myelin sheath in the CNS
The voltage-gated Na+ channels ____ when the cell membrane reaches threshold level as a result of a stimulus
open