Mechanisms of Breathing

What happens to the pressure in the lungs when the thoracic cavity expands?

• decreases

• increases

• stays the same

What happens to the volume in the lungs when the thoracic cavity is made smaller

• decreases

• increases

• stays the same

• decreases pressure

What is the path of an air molecule into the lungs?

• trachea, larynx, bronchioles, bronchus

• larynx, trachea, bronchus, bronchioles

• trachea, bronchus, larynx, bronchioles

• bronchus, pharynx, epiglottis, alveloi

What happens at the alveoli?

• air sacs are made

• the chest is raised

• gaseous exchange

• inhalation

Given the following structures:
1. larynx
2. nasal cavity
3. pharynx
4. trachea
Which of the following is the correct order that air would flow during inhalation

• 1 2 3 4

• 2 3 1 4

• 2 1 3 4

• 4 3 2 1

What happens to the lung pressure before inhalation

• stays the same

• increases

• decreases

What happens to the lung pressure before exhalation

• stays the same

• increases

• decreases

What is the relationship between pressure and volume?

• if volume increases, then pressure increases

• if volume increases, then pressure decreases

• if volume increases, then pressure stays the same

Which intercostal muscles does inspiration and regular expiration use?

• internal intercostals

• external intercostals

Which intercostal muscles does forced expiration use?

• internal intercostals

• external intercostals