Anatomy Week 7 - Muscles of the abdominal region

Question 1

List the abdominal muscles that form the anterior and lateral abdominal wall and the functions.

Answer 1

• External abdominal oblique
• Internal abdominal oblique
• Rectus abdominis
• Transversus abdominis

Functions:
* Protects the internal organs
* Contribute to maintain an erect posture
* Help expiration of the lungs

Question 2

Locate and describe the functions of the external abdominal oblique muscle.

Answer 2

• The largest and most superficial of the 4 muscles.
• Originates from the external surface and inferior borders of the lower eight ribs
• Functions:
• Unilateral contraction causes ipsilateral lateral flexion of the trunk and contralateral rotation
  of the trunk
• Bilateral contraction flexes the trunk anteriorly

Question 3

Locate and describe the functions of the Internal abdominal oblique muscle.

Answer 3

Located: at the thoracolumbar fascia and inserts in the inferior border of the 10th - 12th ribs.

Functions:
- Helping reduce volume of the chest during exhalation.
- Rotates and flex the trunk.

Question 4

Locate and describe the functions of the Rectus Abdominis.

Answer 4

Located: Superior surface of pubis, segmented into three sections.

Functions: Flexes the trunk and compresses the abdominal wall.

Question 5

Locate and describe the functions of the Transversus Abdominis.

Answer 5

The deepest abdominal muscle.

Located: Arises from the deep surface of the lower six costal cartilages. Directly under the Rectus abdominus.

Functions: Stabilizes the lumbar spine and pelvis before movement of the lower and upper limbs.