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Questions and Answers
The term central nervous system refers to _______.
The term central nervous system refers to _______.
brain and spinal cord.
A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.
A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.
interneuron.
Saltatory conduction is made possible by ________.
Saltatory conduction is made possible by ________.
myelin sheath.
Which of the following is NOT a chemical class of neurotransmitter?
Which of the following is NOT a chemical class of neurotransmitter?
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Which of the following is false or incorrect?
Which of the following is false or incorrect?
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Select the correct statement regarding chemical synapses.
Select the correct statement regarding chemical synapses.
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Which of the following correctly describes a graded potential?
Which of the following correctly describes a graded potential?
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Schwann cells are functionally similar to ________.
Schwann cells are functionally similar to ________.
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Immediately after an action potential has peaked, which of the following channels will open?
Immediately after an action potential has peaked, which of the following channels will open?
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An inhibitory postsynaptic potential (IPSP) is associated with ________.
An inhibitory postsynaptic potential (IPSP) is associated with ________.
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Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
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When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.
When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.
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What is the role of tropomyosin in skeletal muscles?
What is the role of tropomyosin in skeletal muscles?
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Which muscle cells have the greatest ability to regenerate?
Which muscle cells have the greatest ability to regenerate?
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Most skeletal muscles contain ________.
Most skeletal muscles contain ________.
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The strongest muscle contractions are normally achieved by _________.
The strongest muscle contractions are normally achieved by _________.
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Which of the following would be recruited later in muscle stimulation when contractile strength increases?
Which of the following would be recruited later in muscle stimulation when contractile strength increases?
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Which of the following is a factor that affects the velocity and duration of muscle contraction?
Which of the following is a factor that affects the velocity and duration of muscle contraction?
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Myoglobin _______.
Myoglobin _______.
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What structure in skeletal muscle cells functions in calcium storage?
What structure in skeletal muscle cells functions in calcium storage?
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What does excess postexercise oxygen consumption represent?
What does excess postexercise oxygen consumption represent?
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Immediately following the arrival of the stimulus at a skeletal muscle cell there is a short period called the ________ period.
Immediately following the arrival of the stimulus at a skeletal muscle cell there is a short period called the ________ period.
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Creatine phosphate functions in the muscle cell by ________.
Creatine phosphate functions in the muscle cell by ________.
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What is the primary function of wave summation?
What is the primary function of wave summation?
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During muscle contraction, myosin cross bridges attach to which active sites?
During muscle contraction, myosin cross bridges attach to which active sites?
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Which of the following surrounds an individual muscle cell?
Which of the following surrounds an individual muscle cell?
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Rigor mortis occurs because ________.
Rigor mortis occurs because ________.
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The oxygen-binding protein found in muscle cells is ______.
The oxygen-binding protein found in muscle cells is ______.
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The contractile units of skeletal muscles are _____.
The contractile units of skeletal muscles are _____.
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Sarcomeres are functional units of _________ muscle.
Sarcomeres are functional units of _________ muscle.
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What is the functional role of the T tubules?
What is the functional role of the T tubules?
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During vigorous exercise, the pyruvic acid is converted to ________.
During vigorous exercise, the pyruvic acid is converted to ________.
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When a muscle is unable to respond to stimuli temporarily, it is in which of the following periods?
When a muscle is unable to respond to stimuli temporarily, it is in which of the following periods?
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In an isotonic contraction, the muscle ________.
In an isotonic contraction, the muscle ________.
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Which of the following is the correct sequence of events for muscle contractions?
Which of the following is the correct sequence of events for muscle contractions?
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The mechanism of contraction in smooth muscles is different from skeletal muscle in that ______.
The mechanism of contraction in smooth muscles is different from skeletal muscle in that ______.
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Which of the following describes the cells of unitary smooth muscle?
Which of the following describes the cells of unitary smooth muscle?
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Which of the following is true about smooth muscle?
Which of the following is true about smooth muscle?
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Smooth muscle is characterized by all of the following EXCEPT _________?
Smooth muscle is characterized by all of the following EXCEPT _________?
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The ability of muscle to shorten forcibly when adequately stimulated is known as _______, and sets muscle apart from other tissue types.
The ability of muscle to shorten forcibly when adequately stimulated is known as _______, and sets muscle apart from other tissue types.
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Which of the following statements is true?
Which of the following statements is true?
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An anaerobic metabolic pathway that results in the production of two net ATPs per glucose plus two pyruvic acid molecules is _______.
An anaerobic metabolic pathway that results in the production of two net ATPs per glucose plus two pyruvic acid molecules is _______.
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Muscle tone is ________.
Muscle tone is ________.
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The sliding filament model of contraction involves _________.
The sliding filament model of contraction involves _________.
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After nervous stimulation stops, what prevents ACh in the synaptic cleft from continuing to stimulate contraction?
After nervous stimulation stops, what prevents ACh in the synaptic cleft from continuing to stimulate contraction?
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Which of the following is the correct order for the phases of a muscle twitch?
Which of the following is the correct order for the phases of a muscle twitch?
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What is the most distinguishing characteristic of muscle tissue?
What is the most distinguishing characteristic of muscle tissue?
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Of the following muscle types, which has the longest muscle cells and has obvious stripes called striations?
Of the following muscle types, which has the longest muscle cells and has obvious stripes called striations?
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Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped, ________.
Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped, ________.
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What part of the sarcolemma contains acetylcholine receptors?
What part of the sarcolemma contains acetylcholine receptors?
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Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of extensibility?
Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of extensibility?
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Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of excitability?
Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of excitability?
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Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of contractility?
Although all the anatomical parts of muscle work together to give it its characteristics, which of the following proteins listed below would be most associated with the characteristics of contractility?
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Oxygen-starved tissues can release chemical signals into the blood that can change the diameter of nearby blood vessels. Which muscle type is responsible for this vasodilation?
Oxygen-starved tissues can release chemical signals into the blood that can change the diameter of nearby blood vessels. Which muscle type is responsible for this vasodilation?
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Of the following items listed below, which is the best description for why skeletal muscle stores glycogen?
Of the following items listed below, which is the best description for why skeletal muscle stores glycogen?
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During development embryonic cells will fuse to form muscle fibers. This will result in ________.
During development embryonic cells will fuse to form muscle fibers. This will result in ________.
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Approximately 80% of a muscle fiber's volume are the myofibrils. This characteristic reflects the muscle's ability to ________.
Approximately 80% of a muscle fiber's volume are the myofibrils. This characteristic reflects the muscle's ability to ________.
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Troponin, a major protein in thin filaments, is a globular protein with three polypeptide subunits. Which of the following is NOT a function of the troponin?
Troponin, a major protein in thin filaments, is a globular protein with three polypeptide subunits. Which of the following is NOT a function of the troponin?
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Curare is a poisonous plant extract. What do you think the symptoms of curare poisoning would look like?
Curare is a poisonous plant extract. What do you think the symptoms of curare poisoning would look like?
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Myasthenia gravis is a disease that results in the loss of ACh receptors at muscle fibers. Which of the following is likely to be a symptom of myasthenia gravis?
Myasthenia gravis is a disease that results in the loss of ACh receptors at muscle fibers. Which of the following is likely to be a symptom of myasthenia gravis?
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Which of the following statements best illustrates the fact that skeletal muscle is voluntary muscle?
Which of the following statements best illustrates the fact that skeletal muscle is voluntary muscle?
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If a muscle fiber were to suddenly and permanently stop producing ATP, which of the following would you expect to happen?
If a muscle fiber were to suddenly and permanently stop producing ATP, which of the following would you expect to happen?
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When a sarcomere contracts and thin filaments move over thick filaments, you would expect to see ________.
When a sarcomere contracts and thin filaments move over thick filaments, you would expect to see ________.
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Addition of more myoglobin to a muscle fiber would have the largest effect on ________.
Addition of more myoglobin to a muscle fiber would have the largest effect on ________.
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Exhaustion of glycogen storage within a muscle fiber would have the biggest effect on ________.
Exhaustion of glycogen storage within a muscle fiber would have the biggest effect on ________.
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Reduction in blood flow to a muscle fiber would have the greatest effect on ________.
Reduction in blood flow to a muscle fiber would have the greatest effect on ________.
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A potential benefit of recruiting slow oxidative fibers for contraction before recruiting fast oxidative and fast glycolytic fibers might be _______.
A potential benefit of recruiting slow oxidative fibers for contraction before recruiting fast oxidative and fast glycolytic fibers might be _______.
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Addition of more mitochondria to a muscle fiber will have the greatest effect on ________.
Addition of more mitochondria to a muscle fiber will have the greatest effect on ________.
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If given the exact same amount of ATP, which of the three fiber types would be able to contract for the longest amount of time?
If given the exact same amount of ATP, which of the three fiber types would be able to contract for the longest amount of time?
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The 100-meter dash is a quick and short run requiring explosive speed. Which of the following is the best explanation for why runners continue to breathe hard after running?
The 100-meter dash is a quick and short run requiring explosive speed. Which of the following is the best explanation for why runners continue to breathe hard after running?
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Nerve impulses are sent to slow the heart's rate of contraction. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
Nerve impulses are sent to slow the heart's rate of contraction. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
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Nerve impulses leading to the brain carry information about cool temperatures on the skin. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
Nerve impulses leading to the brain carry information about cool temperatures on the skin. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
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Nerve impulses leading to skeletal muscle carry information to direct movement. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
Nerve impulses leading to skeletal muscle carry information to direct movement. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
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Cranial nerve II, the optic nerve sends nerve impulses to the brain carrying information about the things we see. These nerve fibers most likely belong to which division of the nervous system?
Cranial nerve II, the optic nerve sends nerve impulses to the brain carrying information about the things we see. These nerve fibers most likely belong to which division of the nervous system?
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The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated. Which of the following cells is most responsible for this?
The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated. Which of the following cells is most responsible for this?
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Some nerve fibers of the peripheral nervous system have the ability to regenerate after damage has occurred. Which of the following cells is most responsible for aiding this regulation?
Some nerve fibers of the peripheral nervous system have the ability to regenerate after damage has occurred. Which of the following cells is most responsible for aiding this regulation?
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It is important for newly developed neurons to form synapses with other neurons. Which cells are most responsible for guiding the formation of these particular junctions?
It is important for newly developed neurons to form synapses with other neurons. Which cells are most responsible for guiding the formation of these particular junctions?
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Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?
Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?
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Like all cells, the neurons' internal organization dictates its function. Neurons have relatively many mitochondria, an extensive network of rough endoplasmic reticulum, and many clusters of ribosomes. These cellular features indicate all of the following EXCEPT ________.
Like all cells, the neurons' internal organization dictates its function. Neurons have relatively many mitochondria, an extensive network of rough endoplasmic reticulum, and many clusters of ribosomes. These cellular features indicate all of the following EXCEPT ________.
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An action potential is regarded as an example of positive feedback. Which of the following examples below best illustrates the positive feedback aspect of an action potential?
An action potential is regarded as an example of positive feedback. Which of the following examples below best illustrates the positive feedback aspect of an action potential?
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The depolarization phase of an action potential is punctuated by the closing of the inactivation gates in the voltage gated sodium ion channels. All of the following are consequences of this inactivation except one. Choose the statement below that is not a consequence of the closing of inactivating gates.
The depolarization phase of an action potential is punctuated by the closing of the inactivation gates in the voltage gated sodium ion channels. All of the following are consequences of this inactivation except one. Choose the statement below that is not a consequence of the closing of inactivating gates.
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During the release refractory period of an action potential, a larger than normal stimulus is needed to cause another action potential. This is due to the fact that ________.
During the release refractory period of an action potential, a larger than normal stimulus is needed to cause another action potential. This is due to the fact that ________.
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If a postsynaptic neuron is stimulated to threshold by spatial summation this implies that ________.
If a postsynaptic neuron is stimulated to threshold by spatial summation this implies that ________.
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If a postsynaptic cell is stimulated to threshold by temporal summation this implies that __________.
If a postsynaptic cell is stimulated to threshold by temporal summation this implies that __________.
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When a neurotransmitter like acetylcholine is acting in an excitatory manner, which of the following is likely a result of the acetylcholine acting on the postsynaptic cell?
When a neurotransmitter like acetylcholine is acting in an excitatory manner, which of the following is likely a result of the acetylcholine acting on the postsynaptic cell?
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When a neurotransmitter like GABA is acting in an inhibitory manner, which of the following is likely a result of the GABA acting on the postsynaptic cell?
When a neurotransmitter like GABA is acting in an inhibitory manner, which of the following is likely a result of the GABA acting on the postsynaptic cell?
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The effect of acetylcholine can be stimulating or inhibiting. Which of the following gives the best explanation for why this is so?
The effect of acetylcholine can be stimulating or inhibiting. Which of the following gives the best explanation for why this is so?
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Which of the following is NOT a function of dendrites?
Which of the following is NOT a function of dendrites?
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Which of the choices below describes the ANS?
Which of the choices below describes the ANS?
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These cells in the CNS have cilia that move in order to circulate cerebrospinal fluid.
These cells in the CNS have cilia that move in order to circulate cerebrospinal fluid.
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What does the central nervous system use to determine the strength of the stimulus?
What does the central nervous system use to determine the strength of the stimulus?
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Bipolar neurons are commonly ________.
Bipolar neurons are commonly ________.
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Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
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Which of the following describes the nervous system integrative function?
Which of the following describes the nervous system integrative function?
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The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________.
The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________.
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Which of the following is NOT a characteristic of neurons?
Which of the following is NOT a characteristic of neurons?
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Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials?
Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials?
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Loss of function in the enzyme acetylcholine esterase would result in which of the following?
Loss of function in the enzyme acetylcholine esterase would result in which of the following?
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Which of the following is NOT a function of the autonomic nervous system?
Which of the following is NOT a function of the autonomic nervous system?
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Collections of nerve cell bodies outside the central nervous system are called ________.
Collections of nerve cell bodies outside the central nervous system are called ________.
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Study Notes
Muscle Contraction and Mechanics
- Tropomyosin inhibits contraction by blocking myosin binding sites on actin.
- Skeletal muscles consist of a mixture of fiber types, allowing for varied functions.
- Strongest contractions occur through maximal stimulus and increased stimulation frequency.
- Myoglobin stores oxygen within muscle cells, vital for aerobic respiration.
- Muscle contraction related to myosin cross bridges attaches to actin filaments.
- Calcium storage in skeletal muscle cells is managed by the sarcoplasmic reticulum.
- Muscle fibers demonstrate contractility, defining their unique capabilities compared to other tissues.
Muscle Fiber Types and Regeneration
- Smooth muscle cells possess the highest regenerative capability compared to skeletal and cardiac muscle.
- Fast glycolytic fibers are most affected by exhaustion of glycogen storage, highlighting their reliance on glucose.
- Slow oxidative fibers are enhanced by additional mitochondria, increasing endurance and energy production.
Muscle Activity and Fatigue
- Anaerobic metabolism leads to lactic acid production when oxygen is scarce.
- Muscle tone corresponds to a state of sustained partial contraction, essential for maintaining posture.
- Excess postexercise oxygen consumption accounts for the oxygen deficit after activity, necessary for recovery processes.
Nervous System Control of Muscle
- Motor units with larger neurons are recruited for stronger stimulation.
- Activation of acetylcholine receptors leads to muscle contraction through chemically gated channels.
- The latency period follows stimulus arrival, involving neurotransmitter release and transmission across synapses.
- Curare poison mimics acetylcholine and causes paralysis by blocking receptor sites without activating them.
- Myasthenia gravis illustrates an autoimmune response leading to weakened muscles due to loss of ACh receptors.
Neuron Structure and Function
- Neurons exhibit features like many mitochondria and extensive endoplasmic reticulum, indicating high energy demands.
- Dendrites receive signals but do not generate impulses away from the cell body.
- Interneurons act primarily to connect other neurons within the nervous system.
- Graded potentials vary in amplitude and are crucial for neuron communication.
Synaptic Transmission and Neurotransmitters
- Acetylcholine functions as an excitatory neurotransmitter for skeletal muscles.
- GABA induces hyperpolarization in postsynaptic cells, serving an inhibitory role.
- Chemical synapses transmit signals across a synaptic cleft, utilizing action potentials to send neurotransmitters.
- Saltatory conduction occurs due to the presence of myelin sheath, facilitating rapid signal transmission.
Ion Channel Dynamics
- Voltage-gated sodium channels open in response to depolarization, driving action potential propagation.
- Potassium channels open immediately after an action potential peaks, promoting repolarization.
Central Nervous System and Support Cells
- Astrocytes regulate the chemical environment for optimal neuron function and guide synapse formation.
- Microglia act as immune cells within the CNS, responding to infectious agents or damage.
- Ependymal cells produce and circulate cerebrospinal fluid, vital for the CNS's protective environment.
Sympathetic vs Parasympathetic Responses
- Parasympathetic impulses slow heart rates, highlighting the balancing act of the autonomic nervous system.
- Sensory (afferent) division neurons convey information about environmental stimuli to the CNS.
Muscle Fiber Characteristics
- Striated muscle fibers are identified by their long, cylindrical shape with multiple nuclei, primarily found in skeletal muscle.
- Elasticity in muscle fibers is attributed to thin (elastin) filaments, while thick (myosin) filaments relate to contractility characteristics.
Neurotransmitter Characteristics
- The effects of neurotransmitters like acetylcholine can vary depending on the receptor type present in the postsynaptic cell, leading to either excitation or inhibition.
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Description
Test your knowledge on muscle function with this set of flashcards. Explore key concepts related to tropomyosin, muscle regeneration, and fiber types in skeletal muscles. Perfect for students in Anatomy and Physiology!
