A&P1.19

Question 1

Muscles of Respiration - L, O, I, A

Diaphragm

Answer 1

L: Between thoracic & abdominal cavities deep
O: Xiphoid process, costal cartilages of inferior 6 ribs and upper 3 lumbar vertebrae
I: Central tendon
A: Initiates inhalation, primary muscle of respiration

• Doesnt attach to bones only to underside of lungs
• Creates a vacuum to help w/ respiration

Question 2

Muscles of Respiration - L, O, I, A

Internal Intercostals

Answer 2

L: Anterior/lateral/posterior ribs deep to external intercostals
O: Lower rib
I: Upper rib
A: Lowers ribs during forced exhalation

oblique fibers opposing external intercostal fiber direction

Question 3

Muscles of Respiration - L, O, I, A

External Intercostals

Answer 3

L: Anterior/lateral/posterior ribs superficial to internal intercostals
O: Upper rib
I: Lower rib
A: Elevates ribs during inhalation

Oblique fibers opposing internal intercostals

Question 4

Attachment Sites for Abdominal Muscles

Inguinal Ligament

Answer 4

ASIS => Pubic symphysis

Question 5

Attachment Sites for Abdominal Muscles

Linea Alba

Answer 5

Xyphoid process => pubic symphysis

Often the ligament torn in pregnancy

Question 6

Abdominal Muscles - L, O, I, A

Transverse Abdominis

Answer 6

L: Anterior abdominal deep
O:
- Inferior surfaces of 7-12th costal cartilages
- Thoracolumbar fascia
- Iliac crest
- 1/3rd of inguinal ligament

I:
- Linea alba via aponeurosis of internal obliques
- Pubic crest
- Conjoint tendon

A: Compresses abdominal contents

Parallel fibers

Question 7

Abdominal Muscles - L, O, I, A

Rectus Abdominis

Answer 7

L: Anterior abdominal superficial
O:
- Xiphoid process
- 5-7th costal cartilages

I:
- Pubic symphysis
- Pubic crest of pubis bone

A:
- Compresses abdominal contents
- Fleixon of torso at waist

Vertical fibers

Question 8

Abdominal Muscles - L, O, I, A

Internal Oblique

Answer 8

L: Anterior abdominal intermediate
O:
- Thoracolumbar fascia
- Anterior 2/3rd of iliac crest
- Lateral 1/2 of inguinal ligament

I:
- Ribs 10-12
- Linea Alba
- Pubis

Question 9

Abdominal Muscles - L, O, I, A

External Oblique

Answer 9

L: Anterior abdominal superficial
O: Exterior surfaes of 5-12th ribs
I:
- Linea alba
- Iliac crest

A:
- Compresses abdominal contents
- Bilateral
**Flexion of torso at waist
- Unilateral
**Lateral flexion and rotation of torso at waist

Oblique fibers opposing internal intercostals

Question 10

Pectoral & Scapula Muscles - L, O, I, A

Serratus Anterior

Answer 10

L: Lateral chest wall superficial
O: Lateral parts of ribs 1-8
I: Medial border of scapula
A: ABduction (protraction) of scapula

Parallel fibers

• Stabilizes scapulas
• Big player in push ups