Describes Bending A Body Part

Extrinsic refers to a muscle that has an origin located in a different body region than its insertion. This means that the muscle originates in one area of the body and inserts or attaches to a different area.

Antagonist muscles are the muscles that have opposite actions to each other. They work in pairs, with one muscle contracting while the other relaxes. This allows for coordinated movement and control of the body. For example, when you bend your elbow, the biceps muscle contracts as the triceps muscle relaxes, and when you straighten your elbow, the triceps muscle contracts as the biceps muscle relaxes. Antagonist muscles play a crucial role in maintaining balance and stability during movement.

Abduction is the term that describes taking a body part away from the midline. It refers to the movement of a body part away from the center of the body or the midline. This movement is usually in the lateral direction, away from the body's midline. Flexion refers to the bending of a joint, extension refers to the straightening of a joint, and adduction refers to the movement of a body part towards the midline.

Adduction is the term that describes bringing a body part toward the midline. This movement involves pulling a body part closer to the center of the body, such as bringing the arm back to the side of the body or bringing the legs together. Flexion refers to bending a body part, extension refers to straightening or extending a body part, and abduction refers to moving a body part away from the midline.

Intrinsic refers to a muscle that has an origin and insertion located in the same body region. This means that both ends of the muscle are within the same area of the body.

A fixator is a muscle that holds an origin stable for another muscle. It helps to stabilize a joint or body part to allow the prime mover muscle to work more efficiently. The fixator muscle contracts isometrically to prevent movement at the origin site, allowing the prime mover muscle to generate more force and perform its intended action effectively.

The main muscle responsible for initiating and carrying out a specific movement or action is known as the prime mover. It is the muscle primarily responsible for generating the force needed to perform the action. The prime mover works in coordination with other muscles, such as the synergist, which assist in the movement, and the fixator, which stabilize the joint or body part. The antagonist, on the other hand, opposes or reverses the action of the prime mover.

Extension is the correct answer because it refers to the movement of bending a body part posteriorly, or straightening it from a flexed position. This movement increases the angle between two body parts, such as extending the leg at the knee joint or straightening the arm at the elbow joint.

An antagonist is a muscle that has the opposite action of another muscle. In other words, when one muscle contracts to perform a certain movement, the antagonist muscle relaxes to allow that movement to occur. For example, when the biceps muscle contracts to flex the elbow, the triceps muscle relaxes as the antagonist, allowing the movement to happen smoothly.

The term "extrinsic" in regard to muscle refers to a muscle that has an origin and insertion located in different body regions. This means that the muscle spans across different parts of the body and is not confined to a single region.

Synergist muscles are the ones that have the same action as the prime mover muscle. They work together with the prime mover to produce a specific movement. While the prime mover is primarily responsible for generating force, the synergist muscles assist and support its action, helping to stabilize and control the movement. Therefore, the term for muscles that have the same action is synergist.

The prime mover refers to the main muscle among a group of synergistic muscles that work together to perform a specific action. It is responsible for initiating and carrying out the desired movement, while the other muscles in the group provide support and assist in the action.

Insertion refers to the attachment of a muscle to the bone or structure that DOES move when the muscle contracts. This means that when the muscle contracts, it pulls on the structure it is attached to, causing movement.

A fixator is a muscle that holds an origin stable for another muscle. This means that it stabilizes the bone or joint that the other muscle is attached to, allowing the other muscle to move more efficiently and effectively. The fixator muscle acts as a support or anchor for the muscle it is stabilizing, ensuring proper movement and function.

Lateral excursion refers to the movement of the jaw to the side. When a person moves their jaw to the side, they are performing a lateral excursion. This movement allows for the grinding and chewing of food, as well as other actions such as speaking and swallowing. Protraction refers to moving a body part forward, retraction refers to moving it backward, and medial excursion refers to the movement towards the midline. None of these actions accurately describe the movement of the jaw to the side.

The term "origin" refers to the attachment of a muscle to a bone or structure that does not move when the muscle contracts. This means that the origin is the fixed point from which the muscle begins its contraction.

Synergists are muscles that have the same action. This means that they work together with the main muscle to perform a specific movement or action. Synergists help to stabilize the movement and provide additional support and strength. They work in coordination with the main muscle to produce a more efficient and effective movement.

Flexion is the term used to describe the bending of a body part anteriorly. This movement decreases the angle between two body parts, typically bringing them closer together. It is commonly observed in joints such as the elbow, knee, and hip.

Retraction refers to the action of pulling or moving a body part backward. In this case, when a person brings part of their body backward, they are performing the muscle action of retraction. Protraction, on the other hand, refers to moving a body part forward. Lateral and medial excursions involve moving a body part sideways. Therefore, retraction is the correct answer in this context.