HUMAN PHYSIO W/ APR & PHILS (LL) PKG
15th Edition
ISBN: 9781265382353
Author: Fox
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Question
Chapter 12, Problem 23RA
Summary Introduction
To review:
The effects of damaged descending motor tracts and the maintenance of muscle tones.
Introduction:
The contraction and relaxation of skeletal muscles occur due cross-bridge formation between the actin-myosin filaments of the muscle fibers. Muscle tone is the condition of relaxed state of muscle during spontaneous excitation through the nervous system. Various kinds of motor neurons are present in the body.
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Chapter 12 Solutions
HUMAN PHYSIO W/ APR & PHILS (LL) PKG
Ch. 12 - Describe the actions of muscles when they...Ch. 12 - Describe the different levels of muscle structure,...Ch. 12 - Define the terms motor unit and innervation ratio...Ch. 12 - Using the concept of recruitment, explain how...Ch. 12 - With reference to the sliding filament theory,...Ch. 12 - Prob. 3bCPCh. 12 - Describe a cycle of cross-bridge activity during...Ch. 12 - Prob. 4bCPCh. 12 - Use a flowchart to show the sequence of events...Ch. 12 - Prob. 5bCP
Ch. 12 - Explain how graded contractions and smooth,...Ch. 12 - Prob. 6bCPCh. 12 - Prob. 7aCPCh. 12 - Describe the relationship between the resting...Ch. 12 - Prob. 8CPCh. 12 - Prob. 9CPCh. 12 - Explain the different causes of muscle fatigue...Ch. 12 - Prob. 11CPCh. 12 - Prob. 12aCPCh. 12 - Describe all of the events that occur from the...Ch. 12 - Prob. 13CPCh. 12 - Explain the significance of reciprocal innervation...Ch. 12 - Describe the functions of gamma motor neurons and...Ch. 12 - Explain how cardiac muscle differs from skeletal...Ch. 12 - Contrast the structure of a smooth muscle cell...Ch. 12 - Distinguish between single-unit and multiunit...Ch. 12 - Describe the events by which depolarization of a...Ch. 12 - Prob. 1RACh. 12 - Prob. 2RACh. 12 - Prob. 3RACh. 12 - Prob. 4RACh. 12 - Prob. 5RACh. 12 - Prob. 6RACh. 12 - Prob. 7RACh. 12 - Electrical excitation of a muscle fiber most...Ch. 12 - The energy for muscle contraction is most directly...Ch. 12 - Prob. 10RACh. 12 - Prob. 11RACh. 12 - Prob. 12RACh. 12 - Which of these types of muscle cells are not...Ch. 12 - Prob. 14RACh. 12 - In an isotonic muscle contraction,...Ch. 12 - Prob. 16RACh. 12 - Prob. 17RACh. 12 - Prob. 18RACh. 12 - Using the concept of motor units, explain how...Ch. 12 - Prob. 20RACh. 12 - Explain why the myosin heads don't bind to the...Ch. 12 - Using the sliding filament theory of contraction,...Ch. 12 - Prob. 23RACh. 12 - Prob. 24RACh. 12 - Prob. 25RACh. 12 - What changes occur in muscle metabolism as the...Ch. 12 - Prob. 27RACh. 12 - Compare cardiac muscle, single-unit smooth muscle,...Ch. 12 - Your friend eats huge helpings or pasta for two...Ch. 12 - Prob. 30RACh. 12 - Prob. 31RACh. 12 - How is electrical excitation of a skeletal muscle...Ch. 12 - Prob. 33RACh. 12 - Prob. 34RACh. 12 - Prob. 35RACh. 12 - Prob. 36RACh. 12 - Refer to figure 12.22 to answer the following...Ch. 12 - Refer to figure 12.22 to answer the following...Ch. 12 - Prob. 39RACh. 12 - Refer to figure 12.22 to answer the following...
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- f) In relation to the size principle of motor unit recruitment, the mechanism of recruitment order is directly related to the: a) Size (cross-sectional area) of muscle fibres. b) Size (diameter) of the motor axons. c) Size of the motoneuron soma and dendrites. d) All of the above.arrow_forwardWhat does the number of fibers contracting at any time depend on?arrow_forwardWhich of the following can respond to increased stimulation with a graded response: a) motoraxon b) whole muscle c) motor unit d) muscle fiberarrow_forward
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- a) Describe how the isolated muscle behaved as the stimulus interval was further decreased. b) What is tetanus? Explain the mechanism behind this phenomenon. c) At which stimulus interval did you observe tetanus? What frequency of stimulation does that correspond to?arrow_forwardIf acetylcholinesterase is defective, or disabled, * A)there will be no muscle contraction B)acetylcholine will not be released from synaptic vescicles inside axon terminal C)acetylcholine will not be able to bind to ACh receptors d)muscle fiber sarcolemma will be overstimulatedarrow_forwardExplain Muscle Activity?arrow_forward
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