Muscular Pt. 2 Muscles of Thorax&Abdomen

Question 1

Diaphram:

Answer 1

Dome shaped muscle b/w thoracic & abdominal cavities

Contraction: flatter/lower inhale

Relaxation: returns to dome shape, exhale

Question 2

Intercostals:

Answer 2

Synergists to diaphragm

Location: b/w ribs
Expand thoacic cage to inhale
Decrease thoacic cage to exhale
Innervation: Intercostal nerve

Question 3

External Obliques:

Answer 3

Most superficial layer of antrolateral abdomin

Muscle fibers run diagonally toward pubis

end in a aponeurosis (broad sheet of CT)

Question 4

External Oblique actions:

Answer 4

Unilateral: rotation of spine
Bilateral: supports abdnominal viscera/ maintain posture

Question 5

Internal Oblique:

Answer 5

Middle layer of anterolateral abdom. wall

Muscle fibers run diagonally, towards sternum
ends in a aponeurosis

Action: rotation of spine, support abdom. viscera, posture

Question 6

Transversus Abdominis:

Answer 6

Deepest layer of anterolateral abdom. wal

Fibers run horiziontally/ transverse

end in a aponeurosis

Action: Supports abdominal organs/viscera, posture

Question 7

Rectus Abdominis:

Answer 7

Superficial antero-medial abdom. wall

fibers run vertically

each rectus is seperated into 3-4 segments

Action: Flexes waist to bend forward for crunches

Question 8

The Linea Alba of the rectus abdominis is:

Answer 8

median-fibrous line that extends from xiphoid to pubic symphysis