Mechanics and physiology of ventilation

During inhalation the diaphragm and ......contract

• skeletal muscles

• intercostal muscles

• thoracic muscles

• smooth muscle

Muscles between the ribs...

• skeletal muscles

• intercostal muscles

• thoracic muscles

• cardiac muscles

Intercostal muscles contact and ..... the size of the thoracic cavity

• Increase

• Decrease

The diaphragm moves slightly

• Downward

• upward

when the diaphragm moves slightly downward it flares the...

• upper portion of the rib cage

• Lower portion of the rib cage

• middle portion of the rib cage

• Thoracic region

During ventilation, when the diaphragm moves slightly downward, the lower portion of the rib cage moves

• down and outward

• up and slightly down

• upward and outward

• downward and forward

When the lower rib cage flares and moves upward and outward, this creates..

• negative pressure

• Positive pressure

Air goes into the lungs with

• Negative pressure

• Positive pressure

• Negative and positive pressure

the diaphragm and intercostal muscles relax during

• exhalation

• inhalation

• respiration

The size of the thoracic cavity decreases during

• respiration

• inhalation

• exhalation