Question

Which structure is highlighted?

Multiple Choice
A. internal abdominal oblique
B. external abdominal oblique
C. anterior rectus sheath
D. rectus abdominis
E. transverse abdominis

Answer 1

To identify the structure highlighted concerning abdominal muscles, one must consider their unique orientations and positions. This eliminates the anterior rectus sheath and rectus abdominis, narrowing the choices to the external oblique, internal oblique, or transversus abdominis muscles.

Step-by-step explanation:

When identifying the structure highlighted in the question involving the abdominal muscles, we need to consider their position and orientation as described in the provided references. The external obliques, internal obliques, and transversus abdominis are each aligned in distinctive ways: the external oblique extends inferiorly and medially, similar to putting fingers into pants pockets; the internal oblique lies perpendicular to the external oblique and extends superiorly and medially, akin to the thumbs being placed in the pockets; and the deepest of the three, the transversus abdominis, encircles the abdomen transversely, much like a belt around pants. The rectus abdominis, commonly known for creating the "six-pack abs" appearance, is enclosed by the rectus sheath, a connective tissue structure, and is positioned medially. Without visualization of the structure in question and the context that the other options (the anterior rectus sheath and rectus abdominis) are not part of the multiple skeletal muscles in the antero-lateral wall, we can use this information to assist in identifying the correct muscle. Given the information that three flat muscles exist in the antero-lateral wall, this eliminates the anterior rectus sheath and the rectus abdominis from the choices, leading us to consider only the options of the external oblique, internal oblique, or transversus abdominis muscles.

Answer 2

The structure highlighted in the image below is the external abdominal oblique.

The answer is option ⇒B

Step-by-step explanation:

The external abdominal oblique is one of the muscles that make up the abdominal wall. It is a broad, flat muscle located on the sides and front of the abdomen.

Here are some key details about the external abdominal oblique:

• 1. Location: The external abdominal oblique muscle is situated on the lateral (outer) sides of the abdomen. It extends from the lower ribs to the pelvis and wraps around the front of the abdomen.

• 2. Appearance: The muscle fibers of the external abdominal oblique run diagonally from the lower ribs towards the midline of the body. They overlap with the fibers of the internal abdominal oblique, which is another muscle layer beneath it.

• 3. Function: The external abdominal oblique has several functions, including trunk rotation, lateral flexion, and compression of the abdominal contents. When both sides of the muscle contract, it aids in flexing the vertebral column forward.

• 4. Structure: Like other muscles, the external abdominal oblique is composed of muscle fibers, connective tissues, nerves, and blood vessels. It is attached to the lower ribs, the linea alba (a fibrous band running down the midline of the abdomen), and the iliac crest (top edge of the pelvis).

Understanding the external abdominal oblique's location, appearance, function, and structure can help in identifying and appreciating its role in the human body.

The answer is option ⇒B