Respiratory A&P

Which of the following is true of the respiratory

structures?

• Gas exchange takes place across all structures of the lower respiratory tract.

• Bronchioles do not collapse because they have large rings of cartilage that provide structural support.

• Alveoli have the greatest surface area

• Alveoli have a thick layer of smooth muscle that determines air flow through the lower respiratory passages.

Activation of beta2-adrenergic receptors and

relaxation of bronchiolar smooth muscle:

• increases air flow to the alveoli.

• increases thoracic volume.

• decreases intrapleural pressure.

• causes exhalation.

Contraction of the diaphragm and intercostal

muscles:

• increases intrapulmonic pressure

• increases thoracic volume

• is caused by the secretion of surfactant

• decreases thoracic volume

Vital Capacity is:

• the same as total lung capacity

• measured during normal quiet breathing

• the maximum volume of air that can be exhaled following maximal inhalation

• aka tidal volume

Which of the following neural structures contains the respiratory control center?

• Broca's Area

• Precentral Gyrus

• Medulla Oblongata

• Hypothalamus