Concept explainers
_____ 1. Which statement is true about an agonist?
- a. It opposes the function of the prime mover.
- b. It is the primary muscle that produces a movement.
- c. It functions primarily to stabilize a joint.
- d. Its muscle fibers are always circular in structure.
Introduction:
Muscle has defined a type of soft tissue found in animals and humans. There are three types of muscles such as striated muscle, non-striated, and cardiac muscle. It is composed of actin and myosin protein filaments that slide into one another and caused contraction of the muscle. It helps to produce force and motion.
Answer to Problem 1DYKB
Correct answer:
Agonist is the primary muscle that produces movement. Therefore, option b. is correct.
Explanation of Solution
Reason for the correct statement:
Option b. is given as “It is the primary muscle that produces a movement”. Agonist is also called a prime mover. This muscle contracts primarily to produce particular movement such as extending the forearm. So, this muscle initiates movement.
Hence, option b. is correct.
Reasons for the incorrect statements:
Option a. is given as “It opposes the function of the prime mover”. Antagonist muscle is a type of muscle that opposes function of the prime mover. Hence, option a. is incorrect
Option c. is given as “Its function primarily to stabilize the joint”. Antagonist stabilizes the joint. Hence, option c. is incorrect.
Option d. is given as “Its muscle fibers are always circular in structure”. Agonist is a type of muscle which only provides shape to muscle. Hence, option d. is incorrect.
Hence, options a., c., and d. are incorrect.
Agonist is a muscle and is also called prime mover as it contracts to initiate the movement of muscles.
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Chapter 11 Solutions
ANATOMY & PHYSIOLOGY LL W/CONNECT ACCESS
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