Concept explainers
Introduction:
The muscular system deals with an organs made of skeletal muscles, cardiac and smooth muscles. It allows movement of the body, circulates blood and maintains posture throughout the body.
Answer to Problem 1TYR
Correct answer:
To make a muscle contract more strongly, the nervous system can activate more motor units. This process is called as recruitment. Therefore, option a is correct.
Explanation of Solution
Justify the reasons for the correct statement:
Recruitment helps in the activating additional motor units in order to complete an increase in contractile strength of a muscle.
Option (a) is given as, “recruitment”
Hence, Option (a)is correct.
Justify reasons for the incorrect statement:
Option (b) is given as, “Summation”
Increases the force of contraction by increasing the frequency of the stimulus of the muscle fibers .Hence, it is incorrect answer.
Option (c) is given as,“Incomplete tetanus”
Itoccurs if the stimulus frequency increases. Muscle tension rises to the high level and relaxation periods are very short and results in a fluttering contraction.Hence it is incorrect answer.
Option (d) is given as,“Twitch”
It is defined as a series of contraction and relaxation is termed as twitching.Hence, it is incorrect answer.
Option (e) is given as,“Concentric contraction”
In concentric contraction, shortening of the muscle occurs with muscle tension hence it is incorrect answer.
Hence, options (b), (c), (d), and (e) are incorrect.
To conclude, recruitment helps in activation of motor units.
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Chapter 11 Solutions
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