Muscles of Inspiration #1

Question 1

What do the muscles of inspiration do?

Answer 1

Directly or indirectly lift the rib cage, which expands the lungs.
We can get rid of this card if you want. It’s not in the study guide.

Question 2

What are the main muscle groups used for inspiration?

Answer 2

• Primary Muscle of Thorax
• Accessory Muscles of Thorax
• Accessory Muscles of the Neck
• Muscles of the Upper Arm and Shoulder
• Back Muscles of Inspiration
  (Not pictured are pectoralis major & Back Muscles)

Question 3

What is the first and most important muscle of inspiration?

Answer 3

• Diaphragm

Question 4

What is the primary muscle of the thorax?

Answer 4

• Diaphragm

Question 5

What does the diaphragm do?

Answer 5

• It pulls the central tendon down and back during inspiration. This expands the lungs in a vertical direction.

Question 6

What are the main structures of the diaphragm?

Answer 6

• A. Central tendon
• B. Aortic hiatus
• C. Esophageal hiatus
• D. Foramen vena cava

Question 7

Central Tendon (diaphragm)

Answer 7

• located in the intermediate region of the diaphragm
• When contracted, the muscle fibers shorten

Question 8

Aortic hiatus (diaphragm)

Answer 8

• Passage for the abdominal (descending) aorta
• Supplies oxygenated blood to all of the abdominal and pelvic organs and the legs

Question 9

Esophageal hiatus (diaphragm)

Answer 9

• Passage for the esophagus and small arteries

Question 10

Foramen vena cava (diaphragm)

Answer 10

• Passage for inferior vena cava (large vein carrying deoxygenated blood to the heart)

Question 11

What are the accessory muscles of the thorax?

Answer 11

A - External Intercostals
B - Internal Intercostals (interchondral portion)
C - Levator Costarum (Brevis) &
D - Levator Costarum (Longus)
E - Serratus Posterior Superior

Question 12

What are the two anterior accessory muscles of the thorax, and what do they do?

Answer 12

• External intercostals
• Internal intercostals
• Elevate the rib cage

Question 13

What are the posterior accessory muscles of the thorax?

Answer 13

• Levators Costarum
• Serratus Posterior Superior

Question 14

What are two parts of the Levators Costarum? What do they do?

Answer 14

• Brevis Portion (shorter)
• Longus Portion (longer)
• Raise ribs (levators elevate, or raise up)

Question 15

What is this Muscle group? What is their function?

Answer 15

• Serrated Posterior Superior
• Elevate ribs