Final answer:
The term 'synergist' describes a muscle that assists the agonist, or prime mover, in generating movement, such as when the brachialis assists the biceps brachii. Synergists can also work as fixators, adding stability and precision to movements.
Step-by-step explanation:
A muscle that aids another by promoting the same movement is known as a synergist. The correct answer is: c) Synergist.
The muscle that assists an agonist in promoting the same movement is a synergist.
In human anatomy and physiology, when discussing muscle movements, the term synergist refers to a muscle that assists the prime mover, or agonist, in performing its action. Several muscles can work together to facilitate movement. The agonist is the main muscle responsible for a particular movement, while the synergist muscle helps the agonist by contributing additional force, as well as reducing unnecessary movement or joint stabilization.
For instance, when lifting a cup, the biceps brachii acts as the prime mover, and the brachialis acts as a synergist, helping the biceps to fulfill this action efficiently. Furthermore, a synergist can function as a fixator, stabilizing the point of origin of the agonist muscle. In contrast, the antagonist muscle performs the opposite action to the agonist, ensuring smooth and controlled movements and maintaining posture. Understanding these roles is crucial in fields such as medicine, physiotherapy, sports science, and when studying the biomechanics of movement.