Intermediate External Intercostal Muscles Quiz

Q1. From which border of a rib do external intercostal fibers arise?

• Medial border of the sternum
• Superior border of the rib above
• Posterior border of the scapula
• Inferior border of the rib above

Q2. Where do external intercostal fibers attach on the rib below?

• Superior border
• Head of the rib only
• Costal groove only
• Inferior border

Q3. How far posteriorly do external intercostal muscles extend?

• Only to the sternum
• Only to the rib angles
• Only to the midaxillary line
• To the rib tubercles

Q4. How far anteriorly does external intercostal muscle tissue extend?

• To the diaphragm
• To the vertebral bodies
• To the lung hila
• To the costochondral junctions

Q5. What replaces the external intercostal muscle anteriorly?

• Endothoracic fascia
• Costal pleura
• Internal intercostal membrane
• External intercostal membrane

Q6. External intercostal fibers run approximately perpendicular to which muscle fibers?

• Rectus abdominis fibers
• Internal intercostal fibers
• Pectoralis major fibers
• Diaphragmatic fibers

Q7. What happens to thoracic dimensions when external intercostals elevate the ribs?

• The diaphragm moves upward actively
• Thoracic dimensions increase
• Thoracic dimensions decrease
• The thorax becomes completely rigid

Q8. Which spinal nerve branches continue as intercostal nerves?

• Anterior rami of thoracic spinal nerves
• Posterior rami of lumbar nerves
• Anterior rami of sacral nerves
• Posterior rami of cervical nerves

Q9. What happens to the intercostal spaces during inspiration without muscular stabilization?

• They become filled with air
• They tend to be drawn inward
• They fuse with adjacent ribs
• They open into the mediastinum

Q10. Which statement best describes the external intercostal membrane?

• It forms the visceral pleura
• It encloses the heart
• It continues the muscle layer anteriorly
• It separates the lung lobes