Location in the Body – BIO 101 Homework Help

The human body encompasses numerous types of muscles placed in every part of the body and some of them acquire their names from their position/location in the body. For instance, the Quadratus lumborum muscle is found in the lower lumbar region of the abdomen. The thoracis muscle is a slim plane of tendinous and muscular fibers which are located in the frontal part of the thoracic cage.

Fascicle Organization

Other muscles are named with reference to its fascicle organization, direction or position within a specific skeletal muscle. The transversus abdominis muscle is basically a muscle stratum of the lateral and anterior abdominal wall and it is called so because of its fibers’ direction. Also, the rectus muscle runs down the elongated axis of a body and they are straight

Terms Indicating Structural Characteristics of the Muscle

The structural characteristic of a muscle is also used to name it. For instance, the triceps brachii muscle is the 3-headed limb muscle which is at the back of the upper arm. Orbicularis oculi muscle is a circular muscle found around the eyeball.

Relative Position

Muscles which are noticeable at the surface of the body are regularly called  superficialis or externus while those found deeper into the body are termed  profundus or internus. Therefore, their relative position in the body determines their name. For instance, the Flexor digitorum superficialis is apparently an extrinsic muscle of the fingers and does the work of flexing. Moreover, the obturator internus muscle is named so because partly it originates from the membrane called obturator and it is found deeper in the pubis region of the body.


Indicating Actions

There are muscles whcich are named with relative to their action in the body. For instance, the flexor muscle is the muscle which flexes or rather decreases the slant/angle between two bones jointed by a joint. The risorius muscle is responsible for facial expression and in this case the term risorius means laughter.